U.S. patent application number 10/166065 was filed with the patent office on 2003-06-19 for system and method for digital data communication.
Invention is credited to Oashi, Masahiro, Shimoji, Tatsuya, Sonoda, Yasuyuki, Yamamuro, Keisei.
Application Number | 20030115222 10/166065 |
Document ID | / |
Family ID | 27310925 |
Filed Date | 2003-06-19 |
United States Patent
Application |
20030115222 |
Kind Code |
A1 |
Oashi, Masahiro ; et
al. |
June 19, 2003 |
System and method for digital data communication
Abstract
A plurality of HTML files having their file names which may
directly be recognized by a filtering part 415 in a data receiver
are stored in a data storage part 411. File names of the HTML files
are assigned to their headers by a data converter 412, and the
files converted and multiplexed are repeatedly transmitted by a
data multiplexing and transmitting part 413. A filtering part 415
selects the data having exact match with the filtering condition. A
data processing part 419 performs data processing required for
generating images, and the images thus generated are displayed on a
screen of the display part 421. The data processing part 419
provides a switching command to a filtering conditions varying part
417 when an operator enters a file to be linked through an input
part 420. The file to be linked is received as a result of changing
the filtering conditions. In this way, the files required can be
received and be displayed dynamically without storing all the HTML
files linked one another even in temporary basis.
Inventors: |
Oashi, Masahiro;
(Kyotanabe-shi, JP) ; Shimoji, Tatsuya;
(Neyagawa-shi, JP) ; Sonoda, Yasuyuki; (Kyoto-shi,
JP) ; Yamamuro, Keisei; (Osaka, JP) |
Correspondence
Address: |
SHAW PITTMAN
1650 TYSONS BOULEVARD
MCLEAN
VA
22102
US
|
Family ID: |
27310925 |
Appl. No.: |
10/166065 |
Filed: |
June 11, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10166065 |
Jun 11, 2002 |
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09477735 |
Jan 5, 2000 |
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6427150 |
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09477735 |
Jan 5, 2000 |
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PCT/JP99/02365 |
May 6, 1999 |
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Current U.S.
Class: |
1/1 ; 707/999.2;
707/E17.005; 707/E17.006 |
Current CPC
Class: |
Y10S 707/99953 20130101;
H04L 65/612 20220501; H04H 20/106 20130101; H04H 20/16 20130101;
H04L 65/613 20220501; H04L 65/611 20220501; G06F 16/10 20190101;
H04H 20/86 20130101; Y10S 707/99945 20130101; Y10S 707/99943
20130101; Y10S 707/99944 20130101; Y10S 707/99931 20130101; H04L
65/70 20220501; H04L 67/02 20130101 |
Class at
Publication: |
707/200 |
International
Class: |
G06F 012/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 6, 1998 |
JP |
HEI10-123193 |
Dec 25, 1998 |
JP |
HEI10-370637 |
Apr 14, 1999 |
JP |
HEI11-107209 |
Claims
What is claimed is:
1. A digital data communication system comprising a transmitter and
a receiver, A) the transmitter including: a1) file storing means
for storing a plurality of files, and a2) transmission means for
repeatedly transmitting the files packetized thereby in accordance
with a transmission protocol, the packetized files uniquely
assigned identifiers; B) the receiver including: b1) selective
receiving means for selectively receiving the packetized files
having predetermined identifiers in accordance with a selecting
condition set therein and outputting data contained in the
packetized files, b2) display data generating means for generating
display data according to the outputted data, and b3) selecting
condition varying means for varying the selecting condition; and C)
wherein c1) the file storing means stores files formed of
self-descriptive data which include a reference command for
referring another file, and wherein the identifier of each file
includes characters directly be selected by the selecting condition
varying means, c2) the display data generating means generates
display data according to the self-descriptive data outputted by
the selective receiving means, and c3) the selecting condition
varying means provides an identifier assigned to a file so as to
obtain the file specified by the reference command in the
self-descriptive data to the selective receiving means.
2. The digital data communication system in accordance with claim
1, wherein the selective receiving means includes receiving means
for receiving the packetized files transmitted and selecting means
for selecting predetermined packetized files out of the packetized
files received by the receiving means.
3. The digital data communication system in accordance with claim
2, wherein the system further comprises display means for
displaying the display data generated by the display data
generating means, and wherein the selecting condition varying means
varies the selecting condition set in the selecting means so as to
select a file specified by the reference command when one of a
plurality of regions displayed on the display means which is
specified by the reference command is selected thereon.
4. The digital data communication system in accordance with claim
2, wherein the system further comprises data converting means for
converting the identifier of the each file and an identifier of the
reference command into characters directly selected by the
selecting means in accordance with a rule for conversion when
identifiers of the files stored in the file storing means are
provided in a form incapable of directly selecting by the selecting
means.
5. A digital data transmitter comprising: file storing means for
storing a plurality of files, each of the files comprising
self-descriptive data which include a reference command for
referring another file, and an identifier of the each file
consisting of characters directly selected by selective receiving
means in a receiver, and transmission means for repeatedly
transmitting the files packetized thereby in accordance with a
transmission protocol, the packetized files being assigned unique
identifiers.
6. The transmitter in accordance with claim 5, wherein the
transmitter further comprises data converting means for converting
the identifier of the each file and an identifier of the reference
command into characters directly selected by selecting means in the
receiver according to a rule for conversion when identifiers of the
files stored in the file storing means are provided in a form
incapable of directly selecting by the selecting means.
7. A digital data receiver comprising: selective receiving means
for selectively receiving the packetized files having predetermined
identifiers in accordance with a selecting condition set therein
and outputting data contained in the packetized files, display data
generating means for generating display data according to the
outputted data, and selecting condition varying means for varying
the selecting condition, wherein the data outputted from the
selective receiving means forms a file comprising self-descriptive
data which include a reference command for referring another file,
and wherein the display data generating means generates display
data according to the self-descriptive data outputted by the
selective receiving means, and wherein the selecting condition
varying means provides an identifier of a file as the selecting
condition to the selective receiving means so as to obtain the file
specified by the reference command in the self-descriptive
data.
8. The receiver in accordance with claim 7, wherein the selecting
condition varying means includes receiving means for receiving the
packetized files being transmitted, and selecting means for
selecting predetermined packetized files out of the packetized
files being received.
9. The receiver in accordance with claim 8, wherein the selecting
condition varying means varies the selecting condition set in the
selecting means so as to select the file specified by the reference
command when one of regions displayed on the display means
according to the display data generated by the display data
generating means, is selected thereon, in the case of including the
reference command in each of the packetized files being
received.
10. The digital data communication system in accordance with claim
2, wherein the files stored in the file storing means are divided
into groups according to the identifiers assigned thereto, and
wherein the selecting means divides the self-descriptive data being
outputted into groups by using the identifiers and outputs the
divided self-descriptive data therefrom.
11. The digital data communication system in accordance with claim
10, wherein the files divided in the same group are transmitted
with the same packet id.
12. The receiver in accordance with claim 8, wherein the files
stored in the file storing means are divided into groups according
to the identifiers assigned thereto, and wherein the selecting
means divides the self-descriptive data being outputted into groups
by using the identifiers and outputs the divided self-descriptive
data therefrom.
13. The receiver in accordance with claim 12, wherein the files
divided in the same group are transmitted with the same packet
id.
14. A computer readable program storage medium, a program stored
therein controlling a digital data receiver having a CPU and
selective receiving component, wherein the selective receiving
component selectively receives packetized files having
predetermined identifiers in accordance with a selecting condition
set therein and outputs data contained in the packetized files, and
wherein the data outputted from the selective receiving component
forms a file comprising self-descriptive data which include a
reference command for referring another file, and wherein the CPU
performs the following steps in accordance with the program; a)
generating display data according to the outputted self-descriptive
data, and b) providing an identifier of a file as the selecting
condition to the selective receiving component so as to obtain the
file specified by the reference command in the self-descriptive
data.
15. The program storage medium in accordance with claim 14, wherein
the reference command is contained in a part of the packetized
files being received, and wherein the selecting condition set in
the selecting means is varied so as to select the file specified by
the reference command when one of regions displayed on the display
means according to the display data, is selected thereon.
16. A digital data receiver comprising a tuner, a transport
decoder, a CPU, and a memory; wherein the tuner receives packets
being transmitted, and wherein the transport decoder selects
packets having predetermined identifiers out of the packets in
accordance with a selecting condition set therein and outputs data
contained in the packets, and wherein the outputted data forms a
file comprising self-descriptive data which include a reference
command for referring another file, and wherein the CPU performs
the following steps: a) generating display data according to the
self-descriptive data outputted from the transport decoder, and b)
providing an identifier of a file as the selecting condition to the
transport decoder so as to obtain the file specified by the
reference command in the self-descriptive data.
17. A computer data signal embodied in a carrier wave, wherein the
data signal forms a program, the program controlling a digital data
receiver which has a selective receiving component and a CPU, the
selective receiving component selectively receiving packets having
predetermined identifiers in accordance with a selecting condition
set therein and outputs data contained in the packets; the data
outputted from the selective receiving component forming a file
comprising self-descriptive data which include a reference command
for referring another file: the CPU performing the following steps
in accordance with the program: a) generating display data
according to the outputted self-descriptive data, and b) providing
an identifier of a file as the selecting condition to the selective
receiving component so as to obtain the file specified by the
reference command in the self-descriptive data.
18. A method of communicating digital data, comprising the steps
of: repeatedly transmitting a plurality of files after packetizing
the files according to a transmission protocol with identifiers
uniquely assigned thereto in a transmitting station, each of the
files comprising self-descriptive data which include a reference
command for referring another file, the identifier of the each file
consisting of characters directly selected by a receiving station;
and performing the following steps in the receiving station,
selectively receiving the packetized files having predetermined
identifiers in accordance with a selecting condition set therein,
and generating display data in accordance with the self-descriptive
data contained in the packetized files, and outputting the
generating data, and varying an identifier of a file as the
selecting condition so as to obtain the file specified by the
reference command in the self-descriptive data.
19. A digital data communication system comprising a transmitter
and a receiver, A) the transmitter including: a1) file storing
means for storing a plurality of files, and a2) transmission means
for repeatedly transmitting the files packetized thereby in
accordance with a transmission protocol, the packetized files
uniquely assigned identifiers; B) the receiver including: b1)
selective receiving means for selectively receiving the packetized
files having predetermined identifiers in accordance with a
selecting condition set therein and outputting data contained in
the packetized files, b2) received data storing means for storing
data contained in the packetized files each having same identifier
in one independent file basis, b3) display data generating means
for generating display data according to the outputted data, and
b4) selecting condition varying means for varying the selecting
condition; and C) wherein c1) the file storing means stores files
formed of self-descriptive data which includes a reference command
for referring another file, c2) the transmission means assigns one
module identifier including characters capable of being read
directly with the selective receiving means to both a reference
file which refers other files and a referred file which is referred
by the reference file, and transmits the reference file and the
referred file, and c3) the display data generating means generates
display data according to the self-descriptive data contained in
the reference file, and generates another display data according to
a desired referred file which is read out thereby from the received
data storing means.
20. A digital data receiver comprising: selective receiving means
for selectively receiving packetized files having predetermined
identifiers in accordance with a selecting condition set therein
and outputting data contained in the packetized files; received
data storing means for storing the outputted data each having same
identifier under a file basis; display data generating means for
generating display data according to the outputted data; and
selecting condition varying means for varying the selecting
condition; wherein the packetized files thus received are one of a
reference file formed of self-descriptive data which includes a
reference command for referring another file and a referred file
which is referred by the reference file, and one identifier
including characters capable of being read directly with the
selective receiving means is assigned to these files, and wherein
display data generating means generates display data according to
the self-descriptive data contained in the reference file, and
generates another display data according to a desired referred file
which is read out thereby from the received data storing means, and
wherein the selecting condition varying means varies the selecting
condition so as to selectively receive packetized files each
assigned same identifier with that of a specific reference file in
order to selectively receive the specific reference file.
21. The receiver in accordance with claim 20, wherein the reference
file is a file including an automatic reference tag.
22. The receiver in accordance with claim 21, wherein the reference
file and the referred file are linked with each other.
23. The receiver in accordance with claim 22, wherein the reference
file and the referred file comprise a unitized file.
24. A computer readable program storage medium in which a program,
for controlling a digital data receiver including a CPU and
selective receiving component which selectively receives packetized
files having predetermined identifiers in accordance with a
selecting condition set therein and outputting data contained in
the packetized files, is stored for operating the digital data
receiver as the digital data receiver defined in claim 20.
25. A method of communicating digital data, comprising the steps
of: repeatedly transmitting a plurality of files stored in a
transmitting station after packetizing the files according to a
transmission protocol with identifiers uniquely assigned thereto in
the transmitting station; and performing the following steps in a
receiving station, selectively receiving the packetized files
having predetermined module identifiers in accordance with a
selecting condition set therein, storing data contained in the
packetized files each having same identifier in one independent
file basis, and generating display data according to the outputted
data, wherein one module identifier including characters capable of
being read directly with the receiving station is assigned to both
a reference file which refers other files and a referred file which
is referred by the reference file in the transmitting station, and
wherein the following steps are performed by the receiving station,
the selecting condition is varied so as to selectively receive
packetized files each assigned same identifier with that of a
specific reference file in order to selectively receive the
specific reference file, and display data is generated according to
self-descriptive data contained in the reference file, and
generates another display data according to a desired referred file
which is read out thereby.
26. A digital data communication system comprising a transmitter
and a receiver, A) the transmitter including: a1) file storing
means for storing a plurality of files, and a2) transmission means
for repeatedly transmitting the files packetized thereby in
accordance with a transmission protocol, the packetized files
uniquely assigned identifiers; B) the receiver including: b1)
selective receiving means for selectively receiving the packetized
files having predetermined identifiers in accordance with a
selecting condition set therein and outputting data contained in
the packetized files, b2) received data storing means for storing
data contained in the packetized files each having same identifier
in one independent file basis, b3) display data generating means
for generating display data according to the outputted data, and
b4) selecting condition varying means for varying the selecting
condition; C) wherein c1) the file storing means stores a plurality
of reference files formed of self-descriptive data which includes a
reference command for referring a plurality of other files, c2) the
transmission means assigns one module identifier including
characters capable of being read directly with the selective
receiving means to the reference files and transmits the reference
files, c3) the display data generating means generates display data
according to the self-descriptive data contained in the reference
files, and generates another display data according to desired
referred files which are read out thereby from the received data
storing means, and c4) the selecting condition varying means uses
the module identifier as the selecting condition.
27. A digital data receiver comprising: selective receiving means
for selectively receiving packetized files having predetermined
identifiers in accordance with a selecting condition set therein
and outputting data contained in the packetized files; received
data storing means for storing data contained in the packetized
files each having same identifier in one independent file basis;
display data generating means for generating display data according
to the outputted data; and selecting condition varying means for
varying the selecting condition; wherein the packetized files thus
received are one of a reference file formed of self-descriptive
data which includes a reference command for referring a plurality
of other files and a referred file which is referred by the
reference file, and wherein one identifier including characters
capable of being read directly with the selective receiving means
is assigned to the referred files through the reference file, and
wherein the display data generating means generates display data
according to the self-descriptive data contained in the reference
file, and wherein the selecting condition varying means varies the
selecting condition so as to selectively receive packetized files
each assigned same identifier with that of a specific reference
file in order to selectively receive the specific reference file in
accordance with data of the reference file.
28. The receiver in accordance with claim 27, wherein same module
identifier with that of the referred files is assigned to the
reference file.
29. A digital data receiver comprising: selective receiving means
for selectively receiving packetized files having predetermined
identifiers in accordance with a selecting condition set therein
and outputting data contained in the packetized files, received
data storing means for storing data contained in the packetized
files each having same identifier in one independent file basis,
display data generating means for generating display data according
to the outputted data, and selecting condition varying means for
varying the selecting condition; wherein the packetized files thus
received are one of a reference file formed of self-descriptive
data which includes a reference command for referring another file
and a referred file which is referred by the reference file, and
one identifier including characters capable of being read directly
with the selective receiving means is assigned to these files, and
wherein display data generating means generates display data
according to the self-descriptive data contained in the reference
file, and generates another display data according to a desired
referred file which is read out thereby from the received data
storing means, and wherein the selecting condition varying means
extracts characters directly be selected by the selective receiving
means out of absolute path assigned to the referred files and
provides the characters to the selective receiving means as the
selecting condition so as to selectively receive packetized files
each assigned same identifier with that of the reference file in
order to selectively receive the reference file.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The entire disclosure of Japanese Patent Application No. Hei
10-123193 filed on May 6, 1998, another Japanese Patent Application
No. Hei 10-370637 filed on Dec. 25, 1998, and another Japanese
Patent Application No. Hei 11-107209 filed on Apr. 14, 1999,
including specification, claims, drawings and abstract is
incorporated herein by reference in its entirety.
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to digital data communication
systems, more specifically to communications of self-descriptive
data.
[0004] 2. Description of the Related Art
[0005] Nowadays, a communication method using the internet is known
as two-way data communications among computers. The principle of
the method will be briefly described hereunder. A plurality of
hyper text markup language (hereinafter referred to as HTML) files
linked with one another are stored into a world wide web
(hereinafter referred to as WWW) server which is connected to the
internet. A demand for transmitting the HTML files stored in the
WWW server is sent thereto from a gathering information computer
which is connected to the internet. The WWW server transmits whole
or a part of the HTML files to the gathering computer in response
to the demand. As a result, data linked with one another and stored
in the WWW server can be transferred.
[0006] Data communication services using satellite broadcasting, on
the other hand, are known as one-way data communications. In
satellite broadcasting, data are transmitted through a moving
picture experts group 2 (hereinafter referred to as MPEG 2) system
standard used for data transmission which has a relatively higher
flexibility than the other two standards in the MPEG 2, such as
MPEG 2 video standard used for video data and MPEG 2 audio standard
used for audio data, out of these three MPEG 2 standards.
[0007] In order to transmit HTML files to the receivers by using
satellite broadcasting, a demand for transmitting desired HTML
file(s) need to be sent to the transmitter.
[0008] To avoid sending the demand, methods described hereunder are
employed in actual data communications protocols such as BITCAST
and ADAMS (TV-Asahi data and multimedia service). A plurality of
files linked with one another are transmitted as one unitized file
by the transmitter. In the receiver, all the files are stored in a
storage device like a hard disk by sequentially storing each of the
files therein. Further, the specified file(s) is displayed in
response to operation of the user by browser software installed in
the receiver. The browser software performs reference operations by
specifying the name of a file(s) stored in a hard disk when there
is HTML tag(s) requiring reference of other file(s) in the
specified file(s) (details of the technology is disclosed in an
article entitled "Special Report from state-of-the-art technology;
The Whole Aspect of the Next Generation Digital Television",
published by Nikkei Business Publications, Inc.)
[0009] In this method, however, all the files must be stored in the
hard disk as well as storing information needed to manage the
directory. In this way, a certain capability for storing this
information is required in the receiver, and the receiver can not
display a desired file(s) until its retrieval is completed.
Further, a number of processing steps need to be performed by the
receiving computer's central processing unit (CPU) for retrieving
the desired file(s) from the stored files.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to overcome the
above mentioned drawbacks on the data communication method, and to
provide a data communication system and a method thereof capable of
selectively receiving selected data out of data consisting of a
plurality of files related one another at a high speed with less
data storing capacities.
[0011] It is another object of the present invention to provide a
data communication system and a method thereof capable of
selectively extracting desired data out of data related with one
another even when the receiver has a small data storing
capability.
[0012] In accordance with characteristics of the present invention,
there is provided a digital data communication system comprising a
transmitter and a receiver,
[0013] A) the transmitter including:
[0014] a1) file storing means for storing a plurality of files,
and
[0015] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0016] B) the receiver including:
[0017] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0018] b2) display data generating means for generating display
data according to the outputted data, and
[0019] b3) selecting condition varying means for varying the
selecting condition; and
[0020] C) wherein c1) the file storing means stores files formed of
self-descriptive data which includes a reference command for
referring another file, and wherein the identifier of each file
includes characters directly selected by the selecting condition
varying means,
[0021] c2) the display data generating means generates display data
according to the self-descriptive data outputted by the selective
receiving means, and
[0022] c3) the selecting condition varying means provides an
identifier assigned to a file so as to obtain the file specified by
the reference command in the self-descriptive data to the selective
receiving means.
[0023] Also, in accordance with characteristics of the present
invention, there is provided a method of communicating digital
data, comprising the steps of:
[0024] repeatedly transmitting a plurality of files after
packetizing the files according to a transmission protocol with
identifiers uniquely assigned thereto in a transmitting station,
each of the files comprising self-descriptive data which include a
reference command for referring another file, the identifier of the
each file consisting of characters directly selected by a receiving
station, and
[0025] performing the following steps in a receiving station,
selectively receiving the packetized files having predetermined
identifiers in accordance with a selecting condition set therein,
generating display data in accordance with the self-descriptive
data contained in the packetized files, outputting the generated
data, and varying an identifier of a file as the selecting
condition so as to obtain the file specified by the reference
command in the self-descriptive data.
[0026] Further, in accordance with characteristics of the present
invention, there is provided a digital data communication system
comprising a transmitter and a receiver,
[0027] A) the transmitter including:
[0028] a1) file storing means for storing a plurality of files,
and
[0029] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0030] B) the receiver including:
[0031] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0032] b2) received data storing means for storing data contained
in the packetized files each having same identifier in one
independent file basis,
[0033] b3) display data generating means for generating display
data according to the outputted data, and
[0034] b4) selecting condition varying means for varying the
selecting condition; and
[0035] C) wherein: c1) the file storing means stores files formed
of self-descriptive data which includes a reference command for
referring another file,
[0036] c2) the transmission means assigns one module identifier
including characters capable of being read directly with the
selective receiving means to both a reference file which refers
other files and a referred file which is referred by the reference
file, and transmits the reference file and the referred file,
and
[0037] c3) the display data generating means generates display data
according to the self-descriptive data contained in the reference
file, and generates another display data according to a desired
referred file which is read out thereby from the received data
storing means.
[0038] In accordance with characteristics of the present invention,
there is provided a method of communicating digital data,
comprising the steps of:
[0039] repeatedly transmitting a plurality of files stored in a
transmitting station after packetizing the files according to a
transmission protocol with identifiers uniquely assigned thereto in
the transmitting station, and
[0040] performing the following steps in a receiving station,
selectively receiving the packetized files having predetermined
module identifiers in accordance with a selecting condition set
therein, storing data contained in the packetized files each having
same identifier in one independent file basis, and generating
display data according to the outputted data,
[0041] wherein one module identifier including characters capable
of being read directly with the receiving station is assigned to
both a reference file which refers other files and a referred file
which is referred by the reference file in the transmitting
station,
[0042] wherein the following steps are performed by the receiving
station, the selecting condition is varied so as to selectively
receive packetized files each assigned same identifier with that of
a specific reference file in order to selectively receive the
specific reference file, display data is generated according to
self-descriptive data contained in the reference file, and
generating another display data according to a desired referred
file which is read out thereby.
[0043] Also, in accordance with characteristics of the present
invention, there is provided a digital data communication system
comprising a transmitter and a receiver,
[0044] A) the transmitter including:
[0045] a1) file storing means for storing a plurality of files,
and
[0046] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0047] B) the receiver including:
[0048] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0049] b2) received data storing means for storing data contained
in the packetized files each having same identifier in one
independent file basis,
[0050] b3) display data generating means for generating display
data according to the outputted data, and
[0051] b4) selecting condition varying means for varying the
selecting condition; and
[0052] C) wherein c1) the file storing means stores a plurality of
reference files formed of self-descriptive data which includes a
reference command for referring a plurality of other files,
[0053] c2) the transmission means assigns one module identifier
including characters capable of being read directly with the
selective receiving means to the reference files and transmits the
reference files,
[0054] c3) the display data generating means generates display data
according to self-descriptive data contained in the reference
files, and generates another display data according to desired
referred files which are read out thereby from the received data
storing means, and
[0055] c4) the selecting condition varying means uses the module
identifier as the selecting condition.
[0056] Further, in accordance with characteristics of the present
invention, there is provided a digital data receiver
comprising:
[0057] selective receiving means for selectively receiving
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0058] received data storing means for storing data contained in
the packetized files each having same identifier in one independent
file basis;
[0059] display data generating means for generating display data
according to the outputted data; and
[0060] selecting condition varying means for varying the selecting
condition;
[0061] wherein the packetized files thus received are one of a
reference file formed of self-descriptive data which includes a
reference command for referring another file and a referred file by
the reference file, and one identifier including characters capable
of being read directly with the selective receiving means is
assigned to these files,
[0062] and wherein the display data generating means generates
display data according to self-descriptive data contained in the
reference file, and generates another display data according to a
desired referred file which is read out thereby from the received
data storing means,
[0063] and wherein the selecting condition varying means extracts
characters directly be selected by the selective receiving means
out of absolute path assigned to the referred files and provides
the characters to the selective receiving means as the selecting
condition so as to selectively receive packetized files each
assigned same identifier with that of the reference file in order
to selectively receive the reference file. While the novel features
of the invention are set forth in a general fashion, both as to
organization and content, the invention will be better understood
and appreciated, along with other objects and features thereof from
the following detailed description taken in conjunction with the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] FIG. 1 is a schematic block diagram showing an overall
structure of a data communication system in accordance with the
present invention.
[0065] FIG. 2 is a simplified conceptual view showing a state of
sending radio waves in satellite broadcasting.
[0066] FIG. 3 is a schematic illustration of a transmitter.
[0067] FIG. 4 is a view showing a data arrangement of a transport
stream transmitted in satellite broadcasting.
[0068] FIG. 5 shows a data structure of packetized data.
[0069] FIG. 6 shows contents of control data of control data
program map table (PMT) 111 for multiplexing the packetized
data.
[0070] FIG. 7 shows contents of control data PMT 114 for
multiplexing the packetized data.
[0071] FIG. 8 shows contents of control data PAT.
[0072] FIG. 9 shows contents of control data network information
table (hereinafter referred to as NIT).
[0073] FIG. 10 is a schematic block diagram of a receiver.
[0074] FIG. 11 is a detailed block diagram illustrating a hardware
structure of the transmitter.
[0075] FIG. 12 shows a file structure stored in an HTML data
storage unit.
[0076] FIG. 13A, FIG. 13B, and FIG. 13C show contents of HTML
files.
[0077] FIG. 14A, FIG. 14B, and FIG. 14C are examples of images
displayed on a screen according to the data stored in the HTML
files.
[0078] FIG. 15 is a correspondence table.
[0079] FIG. 16 is a block diagram showing a typical example of the
hardware structure of a data converter 375.
[0080] FIG. 17A and FIG. 17B show other correspondence tables.
[0081] FIG. 18 is a flow chart for describing steps for creating
the correspondence table with the data converter 375.
[0082] FIG. 19 is a detailed block diagram illustrating the
hardware structure of the receiver.
[0083] FIG. 20 is a functional block diagram of a transport stream
decoder.
[0084] FIG. 21 is a flow chart for describing steps of a receiving
operation control program.
[0085] FIG. 22 is a flow chart for describing steps of a display
program.
[0086] FIG. 23A, FIG. 23B, and FIG. 23C are tables showing
filtering conditions.
[0087] FIG. 24 shows files names after conversion.
[0088] FIG. 25A, FIG. 25B, and FIG. 25C show converted contents of
HTML files.
[0089] FIG. 26 is a flow chart for describing steps for changing a
file name.
[0090] FIG. 27 is a block diagram showing an overall structure of a
digital broadcasting system used in a third embodiment of the
present invention.
[0091] FIG. 28A and FIG. 28B are views showing the structure of the
data in both an HTML file and an U-U object.
[0092] FIG. 29 shows a data structure of packetized data being
transmitted.
[0093] FIG. 30 is a detailed view for describing filtering
conditions.
[0094] FIG. 31 is a schematic block diagram showing the hardware
structure of a data receiver 414.
[0095] FIG. 32 is an overall view of a communication system using
the data receiver 414.
[0096] FIG. 33 shows data contents of a reference file.
[0097] FIG. 34 shows an image displayed according to the contents
of the reference file.
[0098] FIG. 35 shows a hierarchial tree structure of a file stored
in a transmitting station.
[0099] FIG. 36 is a flow chart for describing steps of a display
program.
[0100] FIG. 37 shows data contents of an HTML file in which a
plurality of files are incorporated with one another.
[0101] FIG. 38 shows data contents of another HTML file in which a
plurality of files are incorporated one another.
[0102] FIG. 39 shows data contents of another HTML file in which
referred files are included therein other than automatic reference
tag(s).
[0103] FIG. 40 shows a typical image displayed in accordance with
the reference file depicted in FIG. 39.
[0104] FIG. 41A and FIG. 41B show data contents of an HTML file
which is referred as the referred file in FIG. 39.
[0105] FIG. 42A and FIG. 42B show images displayed according to the
referred file shown in FIG. 41A and FIG. 41B.
[0106] FIG. 43 shows a hierarchial tree structure of a file stored
in the transmitter side.
[0107] FIG. 44 shows data contents of a reference file.
[0108] FIG. 45 shows another hierarchial tree structure of a file
stored in the transmitter side.
[0109] FIG. 46 is a flow chart for describing steps of storing data
into a cache memory.
[0110] FIG. 47 shows a data structure of packetized data being
transmitted.
[0111] FIG. 48A through FIG. 48C show data structure of the data
stored in the cache memory.
[0112] FIG. 49 shows data contents of an HTML file which is
referred as the referred file.
[0113] FIG. 50A and FIG. 50B show images displayed according to the
referred file shown in FIG. 49.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0114] The preferred embodiment of the present invention will be
described herein along with the index shown in below:
1 1. FUNCTION BLOCK DIAGRAMS 1 - 1. Outline of satellite
broadcasting 1 - 1 - 1. State of sending radio waves in satellite
broadcasting 1 - 1 - 2. Outline of transmitter 1 - 1 - 3. Structure
of transport stream 1 - 1 - 4. Outline of receiver 1 - 2. First
embodiment 1 - 2 - 1. Transmitter 1 - 2 - 2. Receiver 1 - 2 - 2 -
1. Hardware structure 1 - 2 - 2 - 2. Receiving operation control
program 1 - 2 - 2 - 3. Display program 1 - 3. Second embodiment 1 -
3 - 1. Data converting operations in transmitter 1 - 3 - 2. Data
receiving operations in receiver 1 - 4. Third embodiment 1 - 4 - 1.
Data transmitter 1 - 4 - 2. Data receiver 1 - 4 - 3. Hardware
structure of data receiver 1 - 5. Fourth embodiment 1 - 6. Other
embodiments.
[0115] 1. Function Blocks
[0116] The system 1 shown in FIG. 1 comprises a transmitter 3 and a
receiver 11.
[0117] The transmitter 3 includes file storing means 5 and
transmission means 7. The file storing means 3 stores a plurality
of files comprising self-descriptive data. A part of the files
include reference commands for referring another files. Identifiers
of the files stored in the file storing means 7 consist of a series
of characters which may directly be recognized with selecting means
15 in the receiver 11. The transmission means 5 repeatedly
transmits the files with the identifiers according to a protocol
after packetizing them.
[0118] The receiver 11 comprises receiving means 14, selecting
means 15, display data generating means 19, and selecting
conditions variation means 17. The receiving means 14 receives the
packets thus transmitted. The selecting means 15 selects only
packets having selective identifiers out of the received packets in
accordance with a selecting condition. The display data generating
means 19 generates display data in accordance with self-descriptive
data included in the selected packets. Further, the selecting
conditions variation means 17 varies the selecting condition so as
to obtain selected file(s) specified by the reference(s) included
in the self-descriptive data. The selecting conditions variation
means 17 also varies the selecting condition in the selecting means
15 so as to obtain selected file(s) specified by the reference
command(s) when an operator of the system selects a display region
specified by the reference command(s) out of all the region
displayed on display means 20.
[0119] 1-1. Outline of Satellite Broadcasting
[0120] One example of applying the present invention to satellite
broadcasting will be described herein. The present invention,
however, may also be applied to other broadcasting methods such as
terrestrial broadcasting, wire broadcasting such as cable
television and the like as long as packetized data are
transmitted.
[0121] 1-1-1. State of Sending Radio Waves in Satellite
Broadcasting
[0122] FIG. 2 shows a simplified conceptual view showing a state of
sending radio waves in satellite broadcasting. Radio waves from a
ground station 1002 are sent to a plurality of ground receivers
(not shown) through a broadcasting satellite 1004. The broadcasting
satellite 1004 sends out a plural number of transport streams 1010,
1020, 1030. Each transport stream is distinguished from the others
by its frequency, plane of polarization and other factors (well
known in the art).
[0123] A plurality of services (analogous to channels in
terrestrial broadcasting) 1011, 1012, 1013, and 1014 being
packetized are multiplexed in the transport stream 1010 under a
time-sharing manner. Similarly, services 1021, 1022, 1023 and 1024,
and services 1031, 1032, 1033 and 1034 are multiplexed respectively
in the transport streams 1020 and 1030. Various control data
representing service information, the present time, and the like,
together are sent out to each of the transport streams in addition
to the packetized data (including video data and audio data).
While, FIG. 2 shows only three transport streams, many more
transport streams may be sent out. Furthermore,.while FIG. 2 shows
a total of four services multiplexed in each transport stream, in
actuality many more services may be multiplexed therein.
[0124] 1-1-2. Outline of Transmitter
[0125] FIG. 3 is a schematic illustration of a transmitter for
generating and transmitting the transport streams described above.
While FIG. 3 shows only the transport stream 1010 for simplicity,
other transport in streams 1020, 1030 are generated thereby in the
same manner.
[0126] Video/audio data of the service 1011 are stored in a data
storing unit 171. These data are compressed by an encoder 181, and
are provided to a multiplexer 160. Similarly, video/audio data of
the services 1012 and 1013 are stored respectively in data storage
unit 172 and 173. Video data for the services are compressed under
the MPEG 2 video standard, and audio data are compressed under the
MPEG 2 audio standard. The data so compressed are provided to the
multiplexer 160.
[0127] In another data storage unit 174, HTML data used for the
service 1014 is stored therein. The data are converted into modules
having object headers by a data converter 184 in accordance with
the MPEG 2 system standard. Module identification (module_id) are
assigned to each of the modules. Details of the assignment will be
described later.
[0128] A control data generator 180 generates control data for
multiplexing the packetized data, the control data for displaying
program information, the control data representing the present time
and other such data. The control data for multiplexing is assigned
for properly recognizing video/audio data in plural services which
are packetized and multiplexed under a time sharing manner.
[0129] The multiplexer 160 outputs a plurality of packets under a
time sharing manner, each consisting of packetized data having a
fixed length as a result of carrying out packetization of the data
provided from the control data generator 180, the encoder 181
through the encoder 183, and that from the data converter 184, as
the transport stream 1010.
[0130] Further, the multiplexer 160 assigns individual module_ids
to section headers of all the packets when the data from the data
converter 184 is packetized. In this embodiment, the last four
digits of a packet are assigned a table_id_extension region (field)
by using the first four digits thereof as a PID because the module
identifiers consist of directory_id and file_id for identifying
module (a total of eight digits) as described later.
[0131] Thus, the packets comprising each file can definitely be
specified without further consideration in the receiver by
distinguishing them using the PID and the table_id_extension.
[0132] A modulator 164 outputs the packets being provided and
modulated thereby as a transport stream. The transport stream thus
outputted is broadcasted to the audience.
[0133] 1-1-3. Structure of Transport Stream
[0134] As shown in FIG. 4, services 1011, 1012 and 1013, each
including video data 81V, 82V and 83V, and audio data 81A, 82A and
83A respectively, service 1014, including HTML or imaging data 84
and a correspondence table 109 are multiplexed in the transport
stream 1010 generated by the transmitter shown in FIG. 3. Details
of the correspondence table 109 will be described later.
[0135] In addition, control data NIT 100, program allocation table
(PAT) 101, and program map table (PMT) 111 through PMT 114 for
multiplexing the packetized data are multiplexed therein. The data
corresponding to the services 1011, 1012, 1013 and 1014 thus
multiplexed can be separated by using these control data as
described later. Control data EIT 121 through EIT 124, each
representing program information, and control data representing the
present time TDT 105, are also multiplexed therein. Other control
data such as scrambling information and others are multiplexed
therein even though these are not illustrated in the figures.
[0136] The control data PMT 111, PMT 112, PMT 113 and PMT 114, and
control data EIT 121, EIT 122, EIT 123 and EIT 124 are the control
data for the services 1011, 1012, 1013 and 1014 respectively.
[0137] Packetization of the control data, the video data, the audio
data, HTML data and the correspondence table is carried out in the
sequence of a line 18a shown in FIG. 4. In other words,
packetization of these data is carried out by the following
sequence: the control data NIT, PAT, PMTs, EITs, TDT, then the
video data 81V, the audio data 81A, the video data 82V, the audio
data 82A, the video data 83V, the audio data 83, and the HTML data
84 and the correspondence table 109. Upon completing the
packetization in the first round, further rounds of packetization
are carried out repeatedly under the same sequence starting from
the control data NIT (see line 18b). The packetization process is
carried out under a certain rule being predetermined (not
shown).
[0138] A basic structure of the packetized data is shown in FIG. 5.
Both the control data and the video/audio data being packetized
have the structure as shown in FIG. 4. PIDs are assigned to the
forefront of each packetized data. PIDs are the references which
are uniquely assigned to each of the packetized data to distinguish
each packetized data from other packetized data. The data content
field packetized object data (e.g. the control data, video/audio
data, HTML data and others).
[0139] Contents of the control data PMT 111 for multiplexing the
packetized data of service 1011 are shown in FIG. 6. PIDs of both
the video data 81V and the audio data 81A of the service 1011 are
stored in the PMT 111. Similar PIDs as to these data in the
services 1012, 1013 are stored respectively to in control data PMT
112, PMT 113.
[0140] As shown in FIG. 7, a PID and a module_id (described later)
of data 84 in the service 1014 are stored in the PMT 114.
[0141] PIDs of PMT 111, PMT 2, PMT 113 and PMT 114, each
corresponding to the services 1011, 1012, 1013 and 1014, are stored
in the control data PAT as shown in FIG. 8.
[0142] Transmission specifications defined by their frequencies,
planes of polarization and the like as to all the transport streams
1010 through 1040, and a list of the services multiplexed in each
of the transport streams are described in the control data NIT as
shown in FIG. 9. This allows the receiver to learn what kinds of
services are included in each of the transport streams.
[0143] 1-1-4. Outline of Receiver
[0144] Functions of the receiver 11 shown in FIG. 1 are outlined
with reference to FIG. 10. In the receiver 11, a desired transport
stream is selected by a tuner 222, and data concerned with a
desired service contained in the selected transport stream is
separated therefrom with a transport decoder 226.
[0145] Further, a micro processing unit (hereinafter referred to as
MPU) 228 sets PIDs of video/audio data of the desired service into
the transport decoder 226. In response to the setting, the
transport decoder 226 outputs the video/audio data of the desired
service. The control data thus separated are provided to the MPU
228 when PIDs of the control data are set into the transport
decoder 226.
[0146] Operations of the receiver 1 which currently receives the
service 1033 contained in the transport stream 1030, and receives a
command to switch it to another service 1012 included in the
transport stream 1010, will be described herein.
[0147] The MPU 228 controls the transport decoder 226 to obtain the
control data NIT (i.e., by setting a PID of the control data NIT
into the transport decoder 226). The description of the control
data NIT tells that the service 1012 is multiplexed in the
transport stream 1010 (see FIG. 9). In response to the description,
the MPU 228 controls the tuner 222 to receive the transport stream
1010. PIDs of video and audio data in the desired service 1012 are
obtained as a result of separating the control data PAT and PMT 112
by controlling the transport decoder 226 with the MPU 228. The MPU
228 controls the transport decoder 226 to output the video and the
audio data of the desired service 1012 by setting filtering
conditions (the conditions for performing filtering) to select
these PIDs into the transport decoder 226.
[0148] Switching of the received service is carried out as
described above.
[0149] The MPU 228, further controls the transport decoder 226 to
obtain the control data EIT when a command for displaying a program
schedule and program information is provided to the MPU 228. In
addition, the MPU 228 controls peripherals to display the program
information and related information in accordance with the control
data EIT thus obtained.
[0150] 1-2. First Embodiment
[0151] 1-2-1. Transmitter
[0152] FIG. 11 is a detailed block diagram illustrating a hardware
structure of the transmitter 3 shown in FIG. 3. The transmitter 3
in this embodiment is used for a digital broadcasting system
compliant with MPEG 2 standard, Digital Storage Media Command and
Control (hereinafter referred to as DSM-CC) specification, and
Digital Video Broadcasting (hereinafter referred to as DVB)
specification for Services Information (hereinafter referred to as
DVB-SI). Definition of MPEG 2 standard is found in the
international standards organization documents ISO/IEC 13818-1 and
ISO/IEC 13818-2. The document ISO/IEC 13818-6 specifies the DSM-CC
specification. Further, the document ETSI ETS 300 468 (which is
similar to document of Association of Radio Industries and
Businesses STD-B2 version 1.0 in Japan) defines the DVB-SI
specification.
[0153] The transmitter 3 is a satellite digital transmitter capable
of transmitting HTML data together with video data and audio data
under a multiplexed format. The structures of services 1012 and
1013 (not shown) are similar to that of service 1011.
[0154] The video data of the service 1011 is stored in a video data
storage unit 311V. The video data are compressed with a video
encoder 331. The video data thus compressed is provided to a
first-in first-out (hereinafter referred to as FIFO) memory 342 as
an elementary stream at a varied rate. The FIFO memory 342 outputs
the elementary stream of video data to a packeting circuit 344 at a
fixed rate.
[0155] The packet circuit 344 segments the elementary stream of the
video data into a plurality of packets each having a fixed length
(e.g. 188 bytes), and writes the packets into a memory 352 as
packetized elementary streams (hereinafter referred to as PES).
PIDs are assigned to each of the PESs as they are written into
memory 352.
[0156] Similarly, audio data of the service 1011 is stored in an
audio data storage unit 311A. The audio data are compressed with an
audio encoder 332, and is provided to another FIFO memory 346. The
compressed audio data are segmented into packets by packet circuit
348. Each packet has a fixed length, and is written into another
memory 354 with its own PID as described above for the video
data.
[0157] A packet multiplex controller 356 reads out PESs of both the
video data and the audio data stored in the memories 352 and 354 in
response to its encoding speed. Also, the controller 356 provides
the PIDs assigned to the PESs of both the video data and the audio
data to a PMT generating circuit 358. The PMT generating circuit
358 generates the control data PMT 111 as a result of receiving the
PIDs. The assigned PIDs of both the video data and the audio data
contained in the service are listed in the control data PMT. Both
the PESs of the video and the audio data being read out from memory
352 and 354 and the corresponding control data PMT are stored in a
memory 362 in a multiplex format under a time-sharing manner.
[0158] Thus, the video and the audio data of the service 1011 are
multiplexed under a time-sharing manner and stored in the memory
362.
[0159] As shown in FIG. 12, the plurality of HTML files include,
e.g., such as "forecast.html","today.html" through "osaka.html" and
the image files include, e.g., "sun.gif" through "rain.gif", both
stored in a directory ".Yen.weather". A plurality of HTML and image
files are stored in a data storage unit 314D. In this way, images
such as those shown in FIG. 14A, can be displayed in accordance
with the HTML files "forecast.html" "today.html" and "osaka.html"
depicted respectively in FIG. 13A.
[0160] A data converter 375 sequentially assigns individual module
identifiers to each of the files. The module identifiers are stored
as an object header for each file. Data converter 375 also creates
a correspondence table between the module_ids thus assigned and
name of the files. In this embodiment, file_ids consisting of a
total of four digits such as id="0001" (expressed in hexadecimal)
are sequentially assigned to the files in the directory "weather".
The sequential assignment is made from the top (.Yen.forecast.html)
through the bottom file (not shown) of the directory "weather" as
described later. Similarly, directory identifiers consisting of
four digits such as id="0001" are assigned to the directory
".Yen.weather" which includes each of the files. Together, the
directory_id and the file_id make up the module_id. This is to
definitely specify each of the files with an absolute path
including name of the directory. For example, a file
".Yen.forecast.html" can definitely be specified as
".Yen.weather.Yen.forecast.html". In this way, a correspondence
table shown in FIG. 15 is created by assigning both the
directory_id and the file_id to each module as its module_id.
[0161] The data converter 375 consist of a combination of hardware
and software structures in this embodiment. FIG. 16 shows a typical
example of the hardware structure of the data converter 375. A
corresponding chart shown in FIG. 17A is stored in a ROM 375r.
Steps performed in a software structure for data conversion used by
the CPU 375c will be described with reference to FIG. 18.
[0162] The CPU 375c initialize the counter i (step S201, in FIG.
18). Then, the file corresponding to the counter i is stored into
the corresponding chart (step S203). For example, the top file
".Yen.forecast.html" of the directory ".Yen.weather" is stored into
a region representing module number 1. Thus, the file
".Yen.weather.Yen.forecast.html" is assigned the module_id
"0001/0001" as shown in FIG. 17B. In this embodiment, the module
identifiers consist of the four digit file_id="0001" and the four
digit directory_id="0001" as described above.
[0163] Next, the CPU 375c determines whether or not all the files
are stored in the corresponding chart (step S207). If files have
not been so stored, the CPU 375c increments the counter i by one,
and stores the next file in the corresponding chart (step S203).
Creation of the corresponding chart is completed when the step S203
is carried out to all the files.
[0164] The corresponding chart thus created is provided to a
packeting component 377, shown in FIG. 11, together with each of
the modules, and is stored in a memory 382 after packetization.
[0165] The data from the data converter 375 is packetized into
packets having a fixed length by the packeting component 377. The
packeting component 377 assigns individual PIDs to the section
headers of all the packets generated. In this embodiment, the first
four digits and the last four digits are respectively assigned as
the PID and the table_id_extension region (field) because the
module identifiers consist of the directory_id and the file_id (a
total of eight digits).
[0166] In this way, the packets making up each file can definitely
be specified without further consideration in the receiver by
distinguishing them using the PID of each packet and the
table_id_extension as a result of distinguishing the modules by the
PID and the table_id_extension of each packet.
[0167] Further, the packeting component 377 also packetizes the
corresponding chart created by the data converter 375 into packets
having a fixed length. In other words, the corresponding chart is
multiplexed as the correspondence table 109 depicted in FIG. 4.
[0168] There are table_id regions (fields) for setting own
table~id, each having a predetermined data length, and
table_id_extension regions (fields) for setting own
table_id_extensions in the sections heads of each packet. Their own
module_ids are stored in the table_id_extension fields as the
table_id_extensions. The details of this relationship will be
described later.
[0169] A packet multiplex controller 384 reads out the data stored
in the memory 382 in response to its encoding speed. Also, the
controller 384 provides PIDs assigned to the data to a PMT
generating circuit 386.
[0170] The PMT generating circuit 386 generates a control data PMT
114 (see FIG. 4) as a result of receiving the PIDs. The PIDs for
each packet related to contained in the service 1014 are listed in
the control data PMT 11. Both the data thus read out from the
memory 382 and the corresponding control data PMT are stored in a
memory 364 in a multiplex format under a time-sharing manner.
Additionally, the PMT 114 contains the module_id into an additional
information field by the circuit 386, the module_id corresponding
to an HTML file comprising a front page displayed initially in the
service 1014. In this way, a table_id_extension "0x0001" is written
to an additional information field in the PMT of the service 1014
as a file_id of the front page when the front page is represented
by file ".Yen.weather.Yen.forecast.html", because the file
".Yen.weather.Yen.forecast.html" is replaced with a file_id "0001"
during the packetization. Also, the file
".Yen.weather.Yen.forecast.html" is replaced respectively with a
PID "0x0001" and a table_id_extension "0x0001" during the
packetization.
[0171] 1-2-2. Receiver
[0172] 1-2-2-1. Hardware Structure
[0173] The hardware structure of the receiver 11 depicted in FIG. 1
is shown in FIG. 19. The receiver 11 functions as a receiver of
satellite broadcasting as well as a device for displaying HTML data
on a monitor.
[0174] The function of the receiver 32 in receiving satellite
broadcasting is similar to that of the conventional broadcasting
receiver, as briefly described below. Radio waves transmitted by
the transmitter are caught with an antenna 131, and the radio waves
are supplied to a tuner 132. The tuner 132 selects one of the
transport streams in accordance with a command of the CPU 147.
Further, the tuner 132 carries out demodulation and
error-correction and other relevant operations, and outputs the
resultant signals to a transport decoder 141.
[0175] The transport decoder 141 only selects (i.e., filters)
predetermined packets out of the packets multiplexed within the
selected transport stream in accordance with PIDs set therein by
the CPU 147. Packetized data for the system are contained in the
multiplexed packets other than control data, video data and audio
data because the system data are also multiplexed together with the
video data and the audio data. The transport decoder 141 identifies
these data in accordance with the data stored in the headers in
each of the files, and both the control data and the system data
are stored in a RAM 144. The RAM 144 stores the packetized data
under the file basis so that the packetized data thus stored forms
to one independent file.
[0176] Filtering procedure carried out in the transport decoder 141
will be described with reference to FIG. 20. Conditions for
performing filtering of data (hereinafter referred to as filtering
conditions) are stored in a filtering conditions storing unit 154.
For example, PIDs, the table_id and table_id_extensions of the
packets to be selected are stored therein. A PID selecting unit 156
selects the packets having predetermined PIDs in accordance with
the filtering conditions stored in the filtering conditions storing
unit 154. The packets of video data and that of audio data, are
respectively outputted to a video decoder 137 and an audio decoder
134. Packets of HTML or image data in a selection format with the
selected packets are outputted to a section data selecting unit 155
shown in FIG. 19. The section data selecting unit 155 only outputs
the packets having predetermined table_id_extensions in accordance
with the filtering conditions stored in the filtering conditions
storing unit 154.
[0177] A conditions varying unit 153 varies filtering conditions
stored in the filtering conditions storing unit 154 in accordance
with a rewrite command outputted by the CPU 147.
[0178] The video data are provided to the video decoder 137 through
the FIFO memory 136 depicted in FIG. 19, and are decompressed or
expanded thereby. The video data are converted into analog signals
with a digital/analog converter (hereinafter referred to as D/A
converter) 138, and the analog signals are displayed on a monitor
140 such as a liquid crystal display, a cathode ray tube and the
like through a video synthesizer 139. The data representing
characters stored in a video RAM (hereinafter referred to as VRAM)
are converted into analog signals with another D/A converter 145,
and the analog signals are provided to the video synthesizer 139.
In this way, characters can be overlapped on images displayed on
the monitor.
[0179] The audio data, on the contrary, are provided to the audio
decoder through another FIFO memory 133, and are decompressed or
expanded thereby. The audio data are outputted through a speaker
135 as actual sound.
[0180] A remote controller 149 stores the following commands such
as initialization of watching, designation of services, instruction
for category search for the program information or the like, and
the controller 149 outputs them to a microcomputer 148 installed in
the main part of the receiver 11.
[0181] The CPU 147 controls the tuner 132, the transport decoder
141 and relevant components in accordance with a receiving
operation control program 142c and a display program 142a both
stored in a ROM 142. These programs may be capable of stand alone
operation, or may require an operating system (such as Windows.TM.
CE by Microsoft.TM. Inc.) as a premise.
[0182] 1-2-2-2. Receiving Operation Control Program
[0183] An embodiment of the receiving operation control program
142c used for carrying out receiving operations will be described
with reference to FIG. 21. Operations necessary to switch the
receiver 11 from receiving the service 1013 contained in the
transport stream 1010, to receiving another service 1011 included
in the transport stream 1010, will be described herein. A switching
command is sent by the remote controller 149 or a control panel
(not shown) to the CPU 147. The switching command is provided to
the CPU 147 through a microcomputer 148. In response to the
switching command, the CPU 147 sets PIDs of the control data PAT
into a register (not shown) for separating the control data in the
transport decoder 141. The PID of the control data PAT has a fixed
value such as "0x0000". In this way, contents of the control data
PAT being separated are stored in the RAM 144 under the control of
the transport decoder 141 (step S11, in FIG. 21). A list of the
services multiplexed in the transport stream currently received are
shown in the contents of the control data PAT (see FIG. 9). The CPU
147 determines that the desired service 1011 is multiplexed in the
transport stream 1010 currently received by referring the list. The
CPU 147 continues processing from step S12 to step S18.
[0184] In the step S18, the CPU 147 obtains PIDs of the control
data PMT in the desired service 1011 in accordance with the
contents of the control data PAT. As a result, the CPU 147
recognizes that id "0x0011" is for a PID of the control data PMT in
the desired service 1011 as shown in FIG. 8. Further, the CPU 147
sets the PID "0x0011" of the control data PMT into the register for
separating the control data in the transport decoder 141 (step
S19). Hence, the control data PMT 111 in the service 1011 can be
separated from other data, and contents of which can be stored in
the RAM 144.
[0185] Next, the CPU 147 recognizes PIDs "0x0022" and "0x0024" of
the video data 81V and the audio data 81A respectively, in
accordance with the PMT for the service 1011 as shown in FIG. 6
(step S20).
[0186] Then, the CPU 147 sets both the PIDs "0x0022" and "0x0024"
into the filtering conditions storing unit 154 (see FIG. 20) in the
transport decoder 141 (step S22). In this way, the transport
decoder 141 can selectively output both the video data 81V and the
audio data 81A, both being required.
[0187] The CPU 147 proceeds its processing to step S13 if the
desired service is not multiplexed in the transport stream
currently received in step S12. Further, the CPU 147 obtains PIDs
of the control data NIT assigned in the control data PAT. In
accordance with the PIDs thus obtained, the CPU 147 obtains the
control data NIT, and determines whether the desired service
contained in any of the transport streams (step S14, step S15).
[0188] The CPU 147 switches a setting of the tuner 34 so as to
receive the transport stream which contains the desired service
(step S16). Then, the CPU 147 obtains the control data PAT of the
transport stream (step S17). Hereafter, steps following to step S18
may be performed, as described above.
[0189] 1-2-2-3. Display Program
[0190] The function for displaying HTML data on the monitor is
accomplished by the CPU 147 and the display program 142a stored in
the ROM 142.
[0191] Data obtained is stored in the RAM 144 when the data is
system data under the control of the transport decoder 141. The CPU
147 starts performing the display program 142a when the system data
is supplied by the transport decoder 141 because the CPU 147
recognizes data written in a section format as system data in this
embodiment.
[0192] Steps performed by the display program 142a for displaying
HTML files will be described with reference to FIG. 19 and FIG.
22.
[0193] At first, a switching command, for switching the operations
to a service in which the HTML files are received, is outputted by
the remote controller 149 in accordance with input of the operator
who refers a program table. As a result of receiving the command,
the CPU 147 varies filtering conditions in the tuner 132 and the
transport decoder 141 respectively.
[0194] For example, the operator selects a service id="001" with
the remote controller 149 when he/she find out a weather forecast
which provides interactive service can be specified by the service
id="001" by referring to the program table.
[0195] Control data PAT is obtained by varying the filtering
conditions of the transport decoder 141 to PID="0x0000" with the
CPU 147 because the PID of the PAT is a fixed value "0x0000". Steps
for obtaining the control data PAT are performed after switching
the tuner 132 so as to receive a transport stream in which a
service specified by the service id="001" is multiplexed as a
result of obtaining the control data NIT thereof when the service
having the service id="001" is multiplexed in the transport stream
other than the transport stream currently received.
[0196] A PMT of the service specified by the service id="001" can
be obtained once the control data PAT is obtained. As a result of
obtaining the PMT, an id of the transport stream in which the
service is multiplexed, PIDs of packets in which data related to
the service is stored, and table_id_extensions of the file which
are displayed at first can automatically be obtained. Under this
logic, the CPU 147 varies filtering conditions in the transport
decoder 141 while switching the tuner 132 in order to receive the
service. In this way, receipt of a service specified by a service
id "001" is started.
[0197] For instance, the CPU 147 varies filtering conditions in the
transport decoder 141 so as to select packets of a PID "0x0001",
that of a table_id "0x3C", and that of a table_id_extension
"0x0001" shown in FIG. 23A when the PID, the table_id, and the
table_id_extension of the service specified by the service id="001"
are respectively "0x0001", "0x3C", and "0x0001" according to the
PMT. The table_id is a fixed value of "0x3C". Further, the numbers
"0x" means that the numbers following thereto are expressed in
hexadecimal in this embodiment.
[0198] Consequently, the transport decoder 141 selects the packets
having their PIDs, table_id, and table_id_extension as "0x0001",
"0x3C", and "0x0001" respectively. Selective reception of the HTML
files shown in FIG. 13A according to the filtering conditions will
be described below as an example.
[0199] The CPU 147 judges whether or not the system data stored in
the RAM 144 comes to one independent file (step S101, in FIG. 22).
In a concrete form, the judgement can be carried out by detecting
whether or not the last block of the system data is received. The
counter i is initialized once the one independent file is received
(step S103). The CPU 147 detects existence of an automatic
reference tag in the HTML data of the file located in i th row
thereof (step S105). The automatic reference tag is defined as
image tags for referring other file(s) regardless of the operations
by the operator. Operations related to the automatic reference tag
will be described later. Since the counter i was initially set to
0, the first time CPU 147 executes step S105, it will move onto
step Sill and generate display data according to the data located
in the i th row. The display data is stored to a VRAM 146, then
converted into analog data by the D/A converter 145. After
conversion to analog data, the display data is provided to the
video synthesizer 139. The video synthesizer 139 outputs display
data which is synthesized with the data from the video decoder 137
thereby to the monitor 140. Hence, a image according to the data
located i th row is displayed on the monitor 140.
[0200] Next, the CPU 147 increments the counter i by one (step
S113), and judges whether or not a tag "</html>" is assigned
to the i th row (step S115). The CPU 147 repeats steps following to
step S105. In this way, images according to data located each of
the rows are displayed sequentially on the monitor 140 (see FIG.
19).
[0201] An image such as that shown in FIG. 14A is displayed on the
monitor 140 when the tag "</html>" is assigned to the i th
row that forms the last row in step S115. The operator operates the
remote controller 149 to obtain detailed information which the
operator desires during the display of such image. For example, the
CPU 147 resets the filtering conditions in step S117 in FIG. 22 as
a result of making a judgment that the reference command(s) for
referring other file(s) is provided thereto when the operator
selects detailed information of "1. Today's weather" (step
S119).
[0202] In a concrete form, the CPU 147 varies the filtering
conditions so as to select a file ".Yen.weather.Yen.today.html" in
accordance with the source codes shown in FIG. 13A when the
operator selects a region displaying the information of "1. Today's
weather" by the remote controller. Practically, the filtering
conditions are varied as described below. The CPU 147 obtains a
module identifier of the file specified by
".Yen.weather.Yen.today.html" by referring to the correspondence
table depicted in FIG. 15. In this case, assignment of PID "0001"
to the file ".Yen.weather.Yen.today.html" is recognized by the CPU
147, and the file having a table_id_extension "0x0002" assigned to
its section header is transmitted. Therefore, the filtering
conditions for the transport decoder 141 are set so as to
selectively receive packets having a table_id_extension "0x0002"
from the conditions to receive the packets having a
table_id_extension "0x0001" as shown in FIG. 23B. In this way,
packets having the table_id_extension "0x0002" can be received. No
variation is required to the PID because it remains the same.
[0203] Thereafter, another image shown in FIG. 14B is displayed on
the monitor 140 according to the HTML file depicted in FIG. 13B by
performing steps following to step S101 repeatedly.
[0204] Hence, a file(s) required for displaying desired image(s)
can be received at each time desired and is displayed by actively
varying the filtering conditions in the transport decoder 141. In
this way, it is not necessary to store all the files for the
display once in the storing part as in the conventional art.
[0205] Another image, according to the HTML file depicted in FIG.
13C which is selectively received in accordance with the filtering
conditions shown in FIG. 23C, is displayed when the operator
selects "OSAKA" during the display of the image shown in FIG. 14B.
An <img src> tag as the automatic reference tag is assigned
in the HTML file thus received. As a result, the CPU 147 performs a
series of steps from step S107 to step S109 in FIG. 22 according to
the row in which the tag is located. The functions performed in
step S109 and step S107 are the same as step S101 and step S119
respectively.
[0206] The CPU 147 additionally sets filtering conditions for the
transport decoder 141 so as to select a desired HTML file(s) when
it detects existence of the automatic reference tag in the HTML
file(s) in step S105. In a concrete form, it is preferred to select
another file specified by "0001/1000.gif" in addition to the HTML
file shown in FIG. 13C because a plurality of conditions may be set
as the filtering conditions for the transport decoder 141. The
filtering conditions for the transport decoder 141 are set so as to
selectively receive packets having a table_id_extension
"0x1000".
[0207] Data in the received packets is temporarily stored in the
RAM 144, and the CPU 147 outputs a display command according to the
stored data. The data thus stored is displayed on the monitor 140
in accordance with the display command.
[0208] As described above, HTML files are transmitted repeatedly
from the transmitter, and the files are received by the receiver
when they are needed for reference, in this embodiment. In this
way, the display of information can be switched dynamically by
selectively receiving the files required solely at the receiver
without storing all the HTML files even on a temporary basis.
[0209] Further, selection of the packets is performed by using a
filtering function of the transport decoder 141. Thus, the CPU 147
may vary the filtering conditions in the transport decoder 141 by
referring the correspondence table being received. Thus, only the
packets contained in the files which are required to be referred
need be extracted.
[0210] In addition, the filtering conditions can also be varied
quickly even when an automatic reference tag(s) is assigned in the
files. In this way, the files required can be displayed
quickly.
[0211] Hence, the following procedures are performed within/between
the transmitter and the receiver respectively in this embodiment.
The transmitter transmits the correspondence table created thereby,
while varying the name of each HTML file in accordance with the
table. Also, the receiver receives the table transmitted by the
transmitter and stores the table therein, and the receiver varies
filtering conditions in the transport decoder by specifying the
required file(s) with the CPU in accordance with the table. In this
way, display of the HTML data transmitted via satellite
broadcasting can be carried out according to interactive operations
even when the receiver has a capability of storing just the
required file(s).
[0212] 1-3. Second Embodiment
[0213] In the first embodiment, the filtering conditions in the
transport decoder 141 are varied by referring the correspondence
table shown in FIG. 15 with the CPU 147. On the contrary, the
second embodiment will disclose a data communication system capable
of actively receiving packets consisting of a desired file(s)
without transmitting the correspondence table. Instead, in this
embodiment HTML data which are automatically changed their file
names and transmitted the correspondence table.
[0214] 1-3-1. Data Converting Operations in Transmitter
[0215] Data converting operations performed by the transmitter will
be described hereunder. The hardware structure of the transmitter
is identical with that of the transmitter described in the first
embodiment. In this embodiment, the data converter 375 shown in
FIG. 11 changes file names of the HTML data into individual
module_ids described in the first embodiment.
[0216] For example, file names shown in FIG. 12 are changed into
four digit numerals expressed in hexadecimal which can directly be
selected by the transport decoder as shown in FIG. 24. File names
".Yen.weather.Yen.forecast.html", ".Yen.weather.Yen.today.html", .
. . are changed respectively into "/0001/0001.html",
"/0001/0002.html" . . . in turn. Further, file names to be referred
in each of the HTML source files are changed so as to correspond
the new file names. For example, a file name
".Yen.weather.Yen.today.html" is changed into "0001/0001.html" in
the tag <A href/weather> as shown in FIG. 25A.
[0217] The data converter 375 is realized by a software structure
using a CPU in this embodiment. Detailed description of the data
converter 375 hardware structure is omitted hereunder because the
hardware structure of the data converter 375 is identical to that
used in the first embodiment. Steps performed in a program for
conversion used by the CPU 375c will be described with reference to
FIG. 26.
[0218] The CPU 375c initializes two counters i and j (step S301, in
FIG. 26). Then, the file corresponding to the counter i is stored
into the corresponding chart (step S303). The function performed in
step S303 is the same as that carried out at step S203, in FIG. 18.
Next, the CPU 375c changes a file name of the file located in i th
row into a module name. For instance, the file name
".Yen.weather.Yen.forecast.html" is changed into the module name
"/0001/0001.html".
[0219] Next, the CPU 375c determines whether or not all the file
names are changed into modules names (step S307), increments the
counter i by one if all the file names are not changed (step S309),
and stores the next file in the corresponding chart (step S303).
Change in file contents data of the file located in j th file in
the correspondence table is performed by using the correspondence
table (step S311) after the steps performed in step S303 and step
S305 are carried out to all the files.
[0220] Next, the CPU 375c determines whether or not these steps are
carried out to all the files (step S313), increments the counter j
by one if these steps are not carried out to all the files (step
S315), and changes the file data. Thus, after finishing step S311
to all the files, the data converting operations performed
automatically are completed.
[0221] The corresponding chart thus created, is provided to the
packeting component 377 shown in FIG. 11 together with each of the
modules, and is stored in the memory 382 after packetization.
[0222] As described above, HTML files are transmitted repeatedly
from the transmitter, and the files are received by the receiver
when they are needed for reference, in this embodiment. In the
transmitter, the module identifier assigned to each of headers are
formed in character strings which can directly be recognized by the
transport decoder so as to select each of the HTML files. A desired
HTML file(s) is extracted by varying the filtering conditions
according to the module identifier in the receiver. In this way,
the display of information can be switched dynamically by
selectively receiving the files required solely at the receiver
without storing all the HTML files even on a temporary basis.
Therefore, the files required can be displayed quickly.
[0223] In addition, the filtering conditions can also be varied
quickly even when an automatic reference tag(s) is assigned in the
files. In this way, only the files required can be displayed
quickly.
[0224] 1-3-2. Data Receiving Operations in Receiver
[0225] Detail description of the receiver is omitted hereunder
because the hardware structure of the receiver is identical to that
used in the first embodiment. In this embodiment, both the file
names (absolute path) and the file names to be referenced are
changed into the file names which can directly be recognized by the
transport decoder. It is, therefore, not necessary for the receiver
to refer the correspondence table. In this way, display according
to a desired HTML file(s) can be carried out without giving too
much load to the CPU as well as not storing all the HTML files in
the receiver even when a plurality of HTML files are linked
thereamong.
[0226] In order to apply the display program shown in FIG. 22 to
the receiver, the step carried out at step S119 may be amended as
follows. For example, the CPU 147 varies the filtering conditions
according to the source codes shown in FIG. 25A so as to select a
file "0001/0002.html" when the operator selects a region on which
"1. Today's weather" is displayed by using the remote controller.
The variation of the filtering conditions may be carried out in
similar manner to that of the first embodiment such that the
table_id_extension "0x0001" is varied to the table_id_extension
"0x0002". No variation is required to the PID because it remains
the same.
[0227] In this embodiment, each of the files is indicated in a full
path format by adding a symbol "/" indicating a directory in which
the file belongs therein. For example, the file "0001.html" in a
directory "/0001" is indicated as "/0001/00001.html".
[0228] In this embodiment the desired HTML file(s) can be extracted
by varying the filtering conditions in the receiver without using
the correspondence table because identifiers of the HTML files are
specified by numbers which can directly be recognized by the
transport decoder. Therefore, all the desired data can be displayed
quickly.
[0229] Further, each of the files belonging to a directory having
the name of ".Yen.weather" is described in this embodiment. Each of
the files can definitely be specified by distinguishing the name of
the directory and the relative path using the PID and the
table_id_extension respectively. The specification of the files is
not limited by that way, it can be carried out by applying plural
number of module identifiers in turn which are prepared as the
correspondence table shown in FIG. 17A in which each module
identifier has different directory name when a plurality of files
belong to different directories. Further, it can also be performed
by applying the module identifier having the same directory
name.
[0230] In addition, a module identifier having different directory
name may be added even when a plurality of files belong to the same
directory. This is advantageous because image data can be specified
by just using PIDs when one of image data contained in a specific
service is free of charge, and another image data in the service
may be charged under a certain rate. In this way, the chargeable
data can be distinguished from the data free of charge by referring
PIDs. For example, in the case of defining data to be charged or
free of charge such that from data "sport1. html" through data
"sport9. html" are free of charge, and from data "spoort10. html"
through data "sport29. html" are chargeable, these data are divide
into two different groups in accordance with their PIDS. By
grouping into two different groups such as a first data group
consist of data "sport1. html" through data "sport9. html" which
belong to the directory "0001" and a second data group formed of
data "spoort10. html" through data "sport29. html" which belong to
the directory "0002", only the data having their PIDs of 0002 can
be charged under a certain rate.
[0231] 1-4. Third Embodiment
[0232] FIG. 27 is a block diagram showing an overall structure of a
digital broadcasting system to be used in a third embodiment of the
present invention. The system comprises a data transmitter 410 and
a data receiver 414.
[0233] 1-4-1. Data Transmitter
[0234] The data transmitter 410 includes a data storing part 411, a
data converting part 412, and a data multiplexing and transmitting
part 413.
[0235] The storing part 411 is composed of a storing device e.g., a
hard disk or an optical disk filing device, for storing digitized
data therein. All the data are made correspondently so as to be
distinguished one another without further consideration by their
file names.
[0236] The converting part 412 converts data read out from the
storing part 411 into down-load data block (hereinafter referred to
as DDB) sections which are capable of being transmitted under the
DSM-CC Data Carousel used as a protocol in an MPEG-2 transport
stream. In a concrete form, the converting part 412 defines
module_id which are specified by the file names stored in the
storing part 411 into table_id_extension fields of section headers
when the data is converted into the DDB sections. Further, the
converting part 412 repeatedly outputs the converted data to the
data multiplexing and transmitting part 413 so as to multiplex them
thereby using the PIDs specified in accordance with the file names.
The module_id are indicated in four digits in hexadecimal because
the file names are expressed in the same manners.
[0237] FIG. 28A shows a structure of the data stored in the storing
part 411. The file name of directory data 530 is "/0001" when it is
expressed in a full path format. The directory data 530 includes a
list of files contained in the directory, in this case, files
"0001.html", "0002.html", and "0003.html" are in the data 530. File
names of the files "0001.html" and "0002.html", and "0003.html" are
expressed respectively in a full path format of "/0001/0001. html",
"/0001/0002.html", and "/0001/0003.html". The file
"/0001/0001.html" is HTML data having a row 532 requiring reference
of a file "/0001/0002.html" and another row 533 requiring reference
of a file "/0001/0003.html".
[0238] The files "/0001/0002.html" and "/0001/0003.html" are HTML
files having data 534 and 535 respectively.
[0239] FIG. 28B shows a data structure of each module for
outputting the directory data and the file data shown in FIG. 28A.
In this embodiment, each of the output data is transmitted as U-U
object because the DSM-CC standard is employed in this embodiment.
The U-U object in the DSM-CC standard is defined as data in which
object headers are assigned to either of the directory data or the
file data.
[0240] In the FIG. 28B, a directory object 536 is a module
including the directory data 530 and having module_id "0000".
Similarly, file object 537 is a module including the HTML file data
531 and having module_id "0001". Further, another file object 538
is a module including the HTML file data 534 and having module_id
"0002". Still further, another file object 539 is a module
including the HTML file data 536 and having module_id "0003".
[0241] FIG. 29 shows a data hierarchy of a DDB section when the DDB
section is defined as a k th block as a result of dividing a module
formed by assigning an object header to the file data 535 having
module_id "0003" into "n" blocks.
[0242] In order to carry out filtering of sections with the
hardware, one U-U object is transmitted as one broadcast inter-ORB
protocol (BIOP) message in this embodiment. Each module is divided
into a plurality of blocks each having a fixed size (only the last
block may be less than the fixed size), and the divided modules are
repeatedly transmitted as DDB messages.
[0243] The DSM-CC standard further defines a format of transmission
on the MPEG-2 transport stream. In order to easily realize the
filtering in section at the receiver, a table_id and a
table_id_extension are assigned to a header of the DDB section.
[0244] Next, data converting operations performed by the data
converter 412 shown in FIG. 27 will be described hereunder. The DDB
section includes a section header field and a DDB message field.
The section header field has a table_id field storing a table_id of
8 bits and a table_id_extension field storing a table_id_extension
of 16 bits. Block data dividing the file object 539 shown in FIG.
28B into a predetermined length (each having 4066 bites) are stored
in the DDB message field.
[0245] Data "0x3C" is set into the table_id field because the
table_id of the DDB section is defined as "0x3C", data "0003"
forming a module_id of the object is set in the table_id_extension
field.
[0246] Further, name of the files consisting the modules indicated
in the full path format is specified by eight digits in hexadecimal
in this embodiment. The data converter 412 assigns the last four
digits (equivalent to data of 16 bits) to the table_id_extension
field because the field is only capable of storing data of 16 bits.
At that time, the data converter 412 outputs a command for
multiplexing the first four digits by using its PID to the data
multiplexing and transmitting part 413. For example, a file
"/0001/0003.html" stored in the storing part 411 is packetized as a
file having its PID "0001" and its table_id_extension "0003".
[0247] The data multiplexing and transmitting part 413 multiplexes
a program allocation table (PAT) and a program map table (PMT) both
defined by the MPEG-2 system, service information defined by the
digital video broadcasting specification for service information
(DVB-SI) standard, an audio video (AV) stream encoded under MPEG-2,
a download information indication (DII) section defined by the
DSM-CC standard all of which are not shown as input thereto, and a
plurality of DDB sections outputted by the data converter 412 by
using PIDs specified. And the data multiplexing and transmitting
part 413 encodes the multiplexed data in response to the
transmission path being used. In a concrete form, a channel code
processing is performed as a channel coding method. For example,
the method includes random processing, error correcting processing,
and interleave processing. Thereafter, stream data obtained as a
result of performing a modulation in digital format such as 64
quadrature amplitude modulation (QAM) is transmitted as radio
waves.
[0248] In this way, the data transmitter 410 can transmit
packetized HTML files repeatedly.
[0249] 1-4-2. Data Receiver
[0250] Next, the structure and operations of the data receiver 414
depicted in FIG. 27 will be described hereunder. The data receiver
414 comprises a filtering part 415, a primary storing part 416
which stores various data, a filtering conditions varying part 417,
and a file obtaining command part 418.
[0251] The filtering part 415 receives a desired transport stream
out of the streams transmitted thereto as radio waves. Section data
having exact match with the filtering conditioned being specified
in the filtering part 415 is stored in the primary storing part
416. The filtering part 415 extracts only the packets having the
specified PIDs and the packets in which both table_id and
table_id_extension are defined out of the received transport
stream.
[0252] The primary storing part 416 may be realized with a RAM, and
it stores data being extracted by the filtering part 415.
[0253] The filtering conditions varying part 417 varies the
filtering conditions stored in the filtering part 415 so as to
extract the desired HTML file(s) in accordance with input of the
operator.
[0254] A data processing part 419, an input part 420, and a display
part 421 are included in the file obtaining command part 418.
[0255] The data processing part 419 generates images for displaying
on a screen of the display part 421 as a result of performing data
processing of multimedia data such as HTML data, bit map data or
audio/video data. Also, the data processing part 419 performs data
processing in accordance with a command signal outputted by the
input part 420, and revises the images generated thereby as a
result of the data processing. Further, the data processing part
419 outputs a command for varying the filtering conditions which
includes name of a desired file to the filtering conditions varying
part 417 when another file is required as a result of performing
the data processing.
[0256] The input part 420 sends signals in response to the inputs
of the operator to the data processing part 419.
[0257] The display part 421 displays the images generated by the
data processing part 419 on its screen.
[0258] Next, functions of the filtering conditions varying part 417
installed in the data receiver are outlined with reference to FIG.
30. As shown in FIG. 30, the file name is composed of a PID and a
module_id both arranged sequentially by using symbols "/" and "."
as delimiters, each of the PID and the module_id being indicated
adjacently into four digit numerals expressed in hexadecimal. For
instance, data "0001" and "0003" respectively indicate a PID and a
module_id in a file name "/0001/0003.html" specified by the file
obtaining command part 418.
[0259] The filtering conditions varying part 417 depicted in FIG.
27 extracts a PID and a module_id out of the file name, and
converts them into the filtering conditions shown in FIG. 30. The
numbers except for both the PID and the module_id are fixed
numbers. Upon setting the filtering conditions in the filtering
part 415, sections, having their values of a table_id and that of
table_id_extension field which are set in a mask bit of the section
header as 1, both respectively "0x3C" and "0003" out of the packets
being transmitted that have their PID "001", are stored in the
primary storing part 416 by using the filtering function of the
transport decoder. All the data contained in the file
"/0001/0003.html" which is transmitted as the DDB sections can be
obtained by setting the filtering conditions.
[0260] Sections consisting one complete file can positively be
selected by referring their section numbers because section numbers
of the sections and number of the last section are stored in the
section header of each section.
[0261] The decision for determining whether or not blocks are part
of a certain module is made by carrying out the following steps.
The number of the last section in the module is stored in the
section headers of the DDB section. Blocks, until one of which has
the same number as the last section number, can be recognized as
one complete module. However, there is a case that one module
possibly consist of more than a total of 256 blocks which is
defined as the maximum number for one module expressed in 8 bits
when a specific module contains a large amount of data because the
last section number is expressed in 8 bits. In such a case, the
decision for determining the last blocks in the module can not be
made because the section number of the DDB section take another
round. In that case, one can make a decision that the blocks having
section numbers more than 256 are also part of the module as a
result of counting the section number.
[0262] 1-4-3. Hardware Structure of Data Receiver
[0263] Next, the hardware structure of the data receiver 414
realized by using a CPU, is shown in FIG. 31. The data receiver 414
comprises a tuner 640, a transport decoder 641, an audio video (AV)
decoder 642, an input interface (I/F) 643, the CPU 644, a ROM 645,
and a RAM 646.
[0264] The tuner 640 selects a transport stream out of the radio
waves in accordance with a command from the CPU 644, and pass the
stream to the transport decoder 641. The transport decoder 641
selects section data having exact match with the filtering
conditions being specified within the transport stream thus
received in accordance with a command from the CPU 644. The section
data thus selected is sent to the RAM 646, and stored therein. In
this embodiment, the transport decoder 641 and the tuner 640
function as the filtering part 415.
[0265] Further, the transport decoder 641 sends PES packets of
audio/video data contained in the transport stream received under
the command from the CPU 644 to the AV decoder 642, the audio/video
data having the specified PIDs. The AV decoder 642 decodes the
audio/video data thus received, and outputs images and sounds.
Further, the AV decoder 642 synthesizes graphic data of on-screen
display (OSD) under the command from the CPU 644, and outputs the
graphic data thus synthesized as images. The outputs of audio/video
from the AV decoder 642 are provided to TV monitor and the like
which displays the images under the NTSC system or the PAL
system.
[0266] The input interface (I/F) 643, comprising an infrared
detector and the like, receives input signals outputted by the
remote controller.
[0267] The CPU 644 controls other hardware in accordance with a
program stored in the ROM 645.
[0268] The filtering conditions varying part 417 is realized by the
AV decoder 642, the input I/F 643 and the program stored in the ROM
645.
[0269] The ROM 645 stores all the programs for controlling the data
receiver 414. The RAM 646 is used for performing the programs
stored in the ROM 645 with the CPU 644. Further, the RAM 646 stores
the data filtered by the transport decoder 641 therein.
[0270] FIG. 32 is an overall view of a communication system using
the data receiver 414 depicted in FIG. 31 as receiver system. In
the communication system, a data receiver 651 is connected with
both an antenna 650 and a television (TV) monitor 653 as shown in
FIG. 32. A selection command is provided to the data receiver 651
in response to the input of the operator into a remote controller
652.
[0271] Data display on the TV monitor 653 will be described
hereunder. Data being processed from the HTML data 531 shown in
FIG. 28A is displayed on the TV monitor 653 as graphic data of
on-screen display.
[0272] Both the characters "Chapter 1" and "Chapter 2", each
contained respectively in the row 532 and the row 533 in FIG. 28A,
are respectively displayed on a region 654 and a region 655 on the
TV monitor 653. The display is called as a hot-spot. In this
example, the region 655 is a region currently selected, and is
highlighted. This state is referred to as a selected status of the
hot-spot.
[0273] The CPU varies filtering conditions in the transport decoder
641 so as to extract the file "/0001/0003.html" when the operator
inputs a command "SET" as a result of making a decision that the
file "/0001/0003.html" is need to be referred.
[0274] As described earlier, the file data can selectively be
divided by using the transport decoder in the filtering part 415.
The divided file data are stored directly in the primary storing
part by providing the data converter 412 and the filtering
conditions varying part 417 respectively to the data transmitter
and the data receiver in this embodiment.
[0275] Although, the files being transmitted are HTML files in the
embodiments described earlier, other data may be used instead of
the HTML files.
[0276] In the system according to the present invention, data of
the desired files(s) can directly be obtained in the primary
storing part from the transmitted data at the data receiver without
using a secondary storing part by providing the data converter and
the filtering conditions variation part respectively to the data
transmitter and the data receiver, the data converter being
operated to convert the file name(s) into data to be recognized by
values converted in accordance with a certain rule, and the
filtering conditions variation part being operated to convert the
file name(s) into filtering conditions in accordance with a certain
rule.
[0277] Further, it is not necessary for the receiver to refer the
correspondence table for varying the filtering conditions in the
transport decoder. It is, therefore, possible to provide a receiver
for broadcasting capable of decreasing the amount of calculation
performed by the CPU as well as saving its data storing
capacity.
[0278] 1-5. Fourth Embodiment
[0279] In each of the embodiments described earlier, file names of
the files are changed into a certain number of digits and a certain
kind of characters capable of reading the transport decoder, and
the file names are assigned to each of the packets as module_id. In
other words, the module_id are uniquely assigned to each of the
packets. In this embodiment, however, the same module_id are
assigned to a plurality of files having a certain relationship
thereamong.
[0280] For example, a reference file "sample.html" shown in FIG. 33
is html data which defines positions of three referred files such
as files "s1. png", "s2. gif", and "s3. jpeg" in the display by
style tags. In this way, a video image shown in FIG. 34 is
displayed on the TV monitor and the like.
[0281] The filtering conditions of rows containing these referred
files "s1. png", "s2. gif", and "s3. jpeg" are varied upon reading
the rows. It might take a certain period of time to display the
images when the variation of the filtering conditions is performed
at an inappropriate timing because each of the packets containing
identical data is repeatedly transmitted within a certain
period.
[0282] In order to solve the drawback, the same module_id are
assigned to the files "s1. png", "s2. gif", and "s3. jpeg" these
having a certain relationship thereamong, and these files are
transmitted. Then, these files are selectively received by using
the module_id thus assigned thereto. In this way, all the referred
files which will be received later can be received with the
reference file(s) thereof as one unitized file so that these files
can be displayed quickly.
[0283] Steps performed in both the transmitter and the receiver, in
order to obtain the files in the above manners, will be described.
Both the reference file and the referred files are stored in the
same directory in the transmitter as shown in FIG. 35. The name of
the directory can be defined as a name using a certain number of
digits, or a certain kinds of characters, and can be read by the
transport decoder. In this embodiment, the module_id is used as the
directory name unlike in the second embodiment in which the file
name is assigned as the module_id when the files are packetized. In
other words, the same module_id "0001" are assigned to the packets
consisting the files "s1. png", "s2. gif", and "s3. jpeg", and then
the packets are transmitted. In order to specify the directory
name, for example, the following procedure is performed such that
only the directory name is converted into a certain kind of
characters having a certain number of digits capable of reading by
the transport decoder so that the receiver may determine which data
should be specified as the module_id. The directory name may also
be specified by judging a part located between "/" being put before
the file name and "/" being put thereafter, and the data existing
therebetween may also be specified as its module_id.
[0284] In order to select a file(s) with the receiver, all the
file(s) having the same id are selectively received thereby and are
temporarily stored in a cache memory having a ceratin capacity and
prepared in the RAM 144. The CPU may conduct a search to find a
referred file when reference is needed.
[0285] FIG. 36 is a flow chart for describing steps for displaying
images in the receiver. One noticeable difference between the steps
in the FIG. 22 and that in this embodiment is that the CPU detects
existence of the referred file within the cache memory in step S106
after detecting existence of the automatic reference tag in step
S105. Another noticeable difference therebetween is that the
directory name of the file is set to the transport decoder as the
filtering conditions in step S107 when no existence of the referred
file within the cache memory is detected in the previous step. For
example, directory name 0001 in which "s1.png" is included is set
to the transport decoder as filtering conditions of the row where a
file src="http://www/dirA/0001/s1.png" is located thereon. In this
way, packets of other files "s2.gif", "s3.jpeg" can also be stored
in the cache memory.
[0286] Similar steps to both steps S106 and S107 are carried out in
steps S118 and S119 such that the CPU detects existence of the
referred file within the cache memory, and then the directory name
of the file is set to the transport decoder as the filtering
conditions when no existence of the referred file within the cache
memory is detected in the previous step.
[0287] Alternatively, both the reference file and the referred file
may be transmitted as one unitized file. For example, a definition
"multipart/mixed" which indicates the file thus defined consisting
of a plurality of files, is allowed in the html format. Under the
circumstance, files depicted in FIG. 35 may be transmitted as one
unitized file shown in FIG. 37 and FIG. 38. In this way, both the
reference file and the referred file can be received at the same
time, so that these files can be displayed quickly.
[0288] On a row 611 in FIG. 37 is a specification statement which
declares the file consist of a plurality of files connected in
series. Another row 615 shows a delimiter of the files connected in
series. In other words, "boundary="boundary-sample" itself forms
the delimiter to the file located therebefore and thereafter in
this case. Another row 621 shows a file name, and yet another row
623 describes a data length such as 928 bytes. Another row 619
shows a data format of the file, that is text data in the html
format. Another row 613 describes both a directory in which the
file is contained, and a computer storing the directory
therein.
[0289] Further, rows 627, 629 indicate contents of the first file
"sample.html".
[0290] In addition, a row 630 contains data related with the second
file "s1.png", rows 631, 633, 635, 637, and 639, respectively shows
a delimiter, a data format of the file, a file name, a data length,
and contents of the second file. In this case, the second file is
formed by image data in the png format.
[0291] Both rows 633 and 635, respectively, show regions related
with files "s21.gif" and "s3.jpeg".
[0292] Hence, files related one another can be displayed quickly as
a result of transmitting these file connected in series as one
unitized file.
[0293] While, existence of the automatic reference tag(s) in which
no operation is required by the operator is detected in this
embodiment, further quick display can be carried out by previously
selecting referred file which need to be inputted by the operator
in addition to the automatic reference tag(s).
[0294] For example, not only the referred files which need to be
inputted by the operator, but also the automatic reference tag(s)
are indicated in the reference file shown in FIG. 39. In a concrete
form, images shown in FIG. 40 are displayed in accordance with the
reference file depicted in FIG. 39. An image shown in FIG. 42A is
displayed in the case of matching the contents of a reference file
"t1.html" specified by a row 651 in FIG. 39 with that of an html
data depicted in FIG. 41A when the operator selects a region where
an image 641 is displayed thereon shown in FIG. 40. Similarly,
another image shown in FIG. 42B is displayed in the case of
matching the contents of a reference file "t2.html" specified by a
row 653 in FIG. 39 with that of an html data depicted in FIG. 41A
when the operator selects a region where an image 643 is displayed
thereon shown in FIG. 40.
[0295] Similarly, selective reception may be carried out by
transmitting files "t1.png", "t1.html", "t2.png", "t2.html", and
"t3.png", these having a certain relationship thereamong by
assigning the same module_id thereto, and receiving them by using
the module_id. Hence, not only the referred files which will be
received later with the automatic reference tag(s), but also other
files not specified by the automatic reference tag(s) may also be
received, so that these files can be displayed quickly.
[0296] Although, all the reference files and all the referred files
are transmitted as one unitized file in this embodiment, a quick
display may be realized as a result of omitting variation of the
filtering conditions for every row by assigning the same module_id
to both a reference file and the referred files and transmitting
them when the reference file contains a plurality of the referred
files. Alternatively, the transmitter may decide whether or not to
provide a different module_id to the referred files in accordance
with frequency in reference of the referred files.
[0297] The same module_id is assigned respectively to the reference
file and the referred files, both stored in the same directory and
transmitted with the module_id in this embodiment. The same
module_id is also assigned respectively to the reference file and
the referred files even when the referred files are stored in a
different directory from that storing the reference file.
[0298] Files "u1.png" and "u2.png", both belonging to a directory
http://www/dirA/0001 which stores a reference file "index._html" as
shown in FIG. 45, are stored in the cache memory when the filtering
conditions are set so as to selectively receive the reference file
"index. html". In this way, the file "u1.png" can be displayed upon
reading the row src="http://www/dirA/0001/u1.png" without varying
the filtering conditions. In order to distinguishably receive a
plurality of files, a plurality of filtering conditions each having
a different condition may be set to the transport decoder for each
of the files, similar to the case in which packets having a
plurality of module_ids are received as one unitized file.
[0299] A program for storing data described in FIG. 46, is stored
in the ROM 142 shown in FIG. 19, and the program is executed in
this embodiment. FIG. 46 is a detailed flow chart for describing
the step of storing data into the cache memory.
[0300] Steps for displaying data according to a reference file
"index.html" depicted in FIG. 44, will be described hereunder. As
shown in FIG. 47, the reference file "index.html" is transmitted as
a plurality of packets under a section basis at the transmission
phase. In this case, file id, not module_id, may be transmitted as
the second item of the DDB message similar to the conventional
manner.
[0301] The reason of transmitting the file_id will be described
hereunder. As described earlier, file names are used instead of
module_id in the third embodiment. Therefore, each of the files can
be distinguished by storing the module_id uniquely assigned to each
module, as the second item of the DDB message as shown in FIG. 29.
In this embodiment, however, the same module_id are assigned to all
the files belonging to a directory. In this way, the receiver can
not distinguish every file when no file id are assigned to the
packets.
[0302] Next, steps for storing data in the cache memory will be
described with reference to FIG. 46. The CPU 147 sets filtering
conditions for the transport decoder 141 so as to selectively
receive packets having their table id extension value of "0001".
The CPU 147 judges whether or not it receives data from the
transport decoder 141 (FIG. 46, step S401), and the CPU 147 reads
out a file name in the DDB message when it receives data from the
transport decoder 141 (FIG. 46, step S403).
[0303] Thereafter, the CPU 147 detects existence of files having
the file name received from the transport decoder 141 within the
cache memory (FIG. 37, S405). A file
"http://www/dirA/0001/index.html" is stored in the cache memory,
because none of such file has been previously stored therein (step
S407). Steps following to step S401 will be repeatedly
performed.
[0304] On the contrary, the file "http://www/dirA/0001/index.html"
is linked with the data which has already been stored in the cache
memory when the CPU finds existence of the file therein because the
file has a file name identical with that of the file received from
the transport decoder 141 (step S409).
[0305] The CPU 147 judges whether or not all the blocks of the file
are stored (step S411), steps following to step S401 will be
repeatedly performed until all the blocks of the file are stored,
signaling completion of receiving the file (step S413). On the
other hand, steps following to step S401 will be repeatedly
performed as an incomplete of receiving the file. Files can be
stored in the cache memory in the receiver under a file basis even
when the same module_id are assigned to a plurality of files.
[0306] As described earlier, each of the files is multiplexed and
repeatedly transmitted in a time series manner by the transmitter.
In this way, files such as "http://www/dirA/0001/u1.png", and
"http://www/dirA/0001/u2.png", both belonging to the same directory
are outputted by the transport decoder 141 when the filtering
conditions set in the decoder are "0001". These data outputted by
the transport decoder 141 are also stored in the cache memory under
the control of the CPU 147 according to the steps shown in the flow
chart depicted in FIG. 46.
[0307] As a result of the data storing, all the files belonging to
the directory selectively received under the filtering condition
"0001", i.e.;
[0308] "http://www/dirA/0001/index.html",
[0309] "http://www/dirA/0001/u1.png", and
[0310] "http://www/dirA/0001/u2.png", are stored in the cache
memory as shown in FIG. 48A.
[0311] Further, the CPU 147 varies the filtering conditions in the
transport decoder 141 so as to selectively receive packets having a
table_id_extension value of "0003" upon reading a row 711 shown in
FIG. 44. In this way, all the files belonging to a directory
selectively received under the filtering condition "0003", are
additionally stored in the cache memory in a sequential manner as
shown in FIG. 48C. The CPU 147 controls display of images depicted
in FIG. 50A according to html data shown in FIG. 49. In this case,
the file "jump.html" may also be considered as a reference file
from the standpoint of a referred file "u1.png" because the file
"jump.html" refers other referred files "u1.png" and so on.
[0312] In order to receive a referred file
"http://www/dirA/0002/jump.html- ", the CPU 147 varies the
filtering conditions in the transport decoder 141 so as to
selectively receive packets having a table_id_extension value of
"0002" according to the description on a row 713 in FIG. 44 when
the operator clicks a region displaying an image 721 depicted in
FIG. 50. In this way, all the files belonging to a directory
selectively received under the filtering condition "0002", are
additionally stored in the cache memory in a sequential manner as
shown in FIG. 48C.
[0313] In order to store upcoming data, the data stored in the
cache memory are erased partially in the order in which data are
stored. In this case, the file "http://www/dirA/0001/index.html"
has already been erased as depicted in FIG. 48C.
[0314] The CPU 147 controls to display an image shown in FIG. 50B
by referring the files
[0315] "http://www/dirA/0001/u1.png",
[0316] "http://www/dirA/0001/u2.png", and
[0317] http://www/dirA/0002/u4.png" those have already been stored
in the cache memory when the referred file "jump.html" specified by
the row 713 depicted in FIG. 44 is html data shown in FIG. 49.
[0318] Thus, display of images according to files belong to several
different directories (groups) can be carried out even when these
files are contained in one reference file. In this way, referred
files and relevant data commonly used in a plurality of reference
files can be stored as a package of data.
[0319] In this case, the referred files and the relevant data may
also be transmitted and be received as one unitized file similar to
that of shown in FIG. 37 and FIG. 38.
[0320] The transmitter in this embodiment may automatically change
directory names into file names having a certain number of digits
and certain kind of characters capable of reading by the transport
decoder similar to the second embodiment. In that case, just the
directory names may be changed, while the file names remains the
same. For example, a part "/music/" preceding to "jump.html" may be
changed into characters "0002" having a certain number of digits
and certain kind of characters capable of reading by the transport
decoder as a result of recognition of the part "/music/" as a
directory name when the directory name of the file
"http://www/dirA/music/jump.html" is changed.
[0321] One unitized file in which a plurality files linked with one
another, as shown in FIG. 37 and FIG. 38 may be transmitted and
received by using one common module_id in the first embodiment
through the third embodiment of the present invention.
[0322] The automatic reference tag(s) in which the image(s) is
pasted thereto is used in this embodiment. Other kinds of automatic
reference tags, for example style tags which define styles of the
reference file may equally be used. In this embodiment, a plurality
of files are transmitted with the same module_id, and the files
having the same module_id are stored in the cache memory. The
filtering conditions are varied when no existence of the files
having the same module_id is detected during the data reference in
the cache memory. The filtering conditions, however, could remain
the same as the filtering conditions currently defined. This could
occur when a file out of plural files contained in a directory, has
not been received yet. In that case, it is not necessary to vary
the filtering conditions of the transport decoder further.
[0323] As described in the previous embodiments, the desired HTML
file(s) can be extracted solely with the transport decoder without
storing the correspondence table by assigning selecting conditions
for specifying at least one or plural files to the header field of
the packets, the selecting conditions including a certain number of
digits and certain kinds of characters capable of directly reading
by the transport decoder.
[0324] 1-6. Other Embodiments
[0325] Selection of the referred file with the transport decoder
can further be accelerated in the first embodiment through the
third embodiment by previously detecting the existence thereof
within the reference file and then varying the filtering conditions
in the transport decoder as the existence detected, rather than
upon completion of data recognition for each row.
[0326] Although, files are transmitted through both the DSM-CC
object carousel and the DSM-CC data carousel on the MPEG 2
transport stream, any protocols capable of performing similar data
processing may be used.
[0327] Though, the file name being converted is indicated with both
a PID and a module_id as a series of characters in the embodiments
described earlier, the PID may be retrieved from the PAT and the
PMT, or may also be retrieved from a combination of other
identifiers selected at an option which allows the similar data
processing.
[0328] The transmitter repeatedly transmits all the files, and the
receiver obtains a desired file(s) by varying the filtering
conditions in filtering means and displays it. In this way, it is
possible to provide a data communication system and a method
thereof in which it appears to the operator that the information is
obtained in the receiver in interactive ways according to the
operations by him/herself without outputting a command for
transmission to the transmitter.
[0329] Although, the transmission of digital data performed in the
satellite broadcasting has been described in the embodiments
described earlier, the transmission of digital data in the present
invention may also be applied to digital terrestrial broadcasting,
and wire broadcasting such as cable television in similar
manners.
[0330] While module identifiers of HTML files, making up the front
page being displayed initially in the services, are assigned in the
control data PMT in the embodiments described earlier, the module
identifiers may be stored in a storing part of the transmitter as
fixed values. For example, they may be set instead of the
table_id_extension of a file being transmitted initially when the
operator switches the service currently received to some other
service.
[0331] The HTML files comprising the front page may be transmitted
to the receiver in a shorter period of time than other files during
the repeated transmission. This is because less time lag for
entering the service is preferred, and entering in the service is
not allowed without the HTML files comprising the front page.
[0332] In the embodiments described earlier, the transport decoder
selects a desired file(s) by referring to both the PIDs and the
table_id_extensions assigned to the files being transmitted by the
transmitter because all the files belong to the directory
".Yen.weather", and for example, the file name is indicated as
/0001/0001.html in the correspondence table. The transport decoder
may select the desired file(s) by using one of the PIDs and the
table_id_extensions. The transport decoder may select the desired
file(s) by using either one of the PIDs or the table_id_extensions.
Further, the transport decoder may use the table_id in addition to
both the PIDs and the table_id_extensions. In other words, any
identifiers which may directly be recognized by the transport
decoder can be used even when they are stored in other regions in
the headers.
[0333] In the first embodiment, HTML data was transmitted as a
single service, i.e., without video data and audio data. However,
in another embodiment, HTML data can be transmitted with video data
and audio data, together as one service, and the service may be
displayed on the monitor after of synthesizing the data.
[0334] Further, data transmission of the HTML data has been
described in aforementioned embodiments, other self-descriptive
data such as standard generalized markup language (SGML) data or
extensible markup language (XML) data may also be adopted to the
present invention in similar manner. In addition, image data which
is referred by the HTML data, may be generated in other formats,
such as JPEG (.jpg) format than the graphics interchange format
(.gif) used in the earlier embodiments. Although, a tag
<HREF> is employed as a reference command(s) for referring
other file(s) in the earlier embodiments, other commands may also
be used in similar manner.
[0335] In order to select a specific region displayed on the
monitor, the operator moves the cursor freely on the monitor in the
earlier embodiments. The control of the cursor depend on the
operating system (not shown) installed in the receiver. The control
may also be performed under the display program.
[0336] The movement of the cursor may be restricted so as to move
within a selectable region alone. The CPU detects that a region is
selected in the case of inputting the command "SET" by the operator
during a period in which the region is specified as a selectable
region when images are displayed on the monitor according to a
specific HTML file. For example, a region located at the upper left
of the monitor is considered as the selected region when the
command "SET" is inputted by the operator. On the contrary, a
region located right under the region currently selected may be
considered as the selected region when the operator enters a
command to move the cursor downwardly in the case of varying
filtering conditions. Similar manners can also be adopted to all
other directions for detecting the selected region. The selected
region can be specified by detecting the direction in the command
inputted with the remote controller by using all the coordinates
being stored.
[0337] In the earlier embodiments, module identifiers of HTML
files, comprising the front page being displayed initially in the
services, are assigned to the additional information fields in the
control data PMT. However, the module identifiers of the HTML files
themselves may be assigned to the additional information fields in
the control data PMT. For example, ".Yen.weather.Yen.forecast.html"
is stored in the additional information fields when a file
".Yen.weather.Yen.forecast.html" is the front page displayed
initially in the service. In that case, the filtering conditions in
the transport decoder can be set by using a module identifier
obtained from the correspondence table shown in FIG. 15.
[0338] While, unencoded data are transmitted by the transmitter in
the earlier embodiments, the data being transmitted may be
scrambled by the transmitter and decoded with the receiver.
[0339] Both a computer software and the CPU are used for realizing
functions of the block diagram shown in FIG. 1 in the above
embodiments, there is no limitation of realizing any of the
functions by a computer hardware. In addition, a part of the
functions or all of these may be realized by a computer hardware
such as logic circuits or the like.
[0340] In the embodiment described earlier, the display program is
stored in the ROM. Alternatively, the display program can also be
installed once in computer readable data storing mediums such as IC
cards or CD-ROMs, and then storing the program in a nonvolatile
memory through an IC card drive or a CD-ROM drive. Further, the
display program may be downloaded into the nonvolatile memory
through a communication line.
[0341] The program may also be incorporated with carrier waves and
the resulting data may be transmitted as computer data signals.
[0342] 1) The digital data communication system according to the
present invention is characterized in that, the system comprises a
transmitter and a receiver,
[0343] A) the transmitter including:
[0344] a1) file storing means for storing a plurality of files,
and
[0345] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0346] B) the receiver including:
[0347] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0348] b2) display data generating means for generating display
data according to the outputted data, and
[0349] b3) selecting condition varying means for varying the
selecting condition,
[0350] C) wherein c1) the file storing means stores files formed of
self-descriptive data which includes a reference command for
referring another file, and wherein the identifier of each file
includes characters directly being selected by the selecting
condition varying means,
[0351] c2) the display data generating means generates display data
according to the self-descriptive data outputted by the selective
receiving means, and
[0352] c3) the selecting condition varying means provides an
identifier assigned to a file so as to obtain the file specified by
the reference command in the self-descriptive data to the selective
receiving means.
[0353] Thus, the files formed of self-descriptive data which
includes the reference command for referring another file are
repeatedly transmitted by the transmitter, and the receiver
selectively receives desired files in accordance with the selecting
condition set therein and the receiver generates display data
according to the self-descriptive data. In this way, the display
data can be displayed on a display means. Also, the selecting
condition is varied so as to obtain the file specified by the
reference command in the self-descriptive data, so that the files
required for display can be received. In this way, the files solely
required for display can be displayed on the display means without
storing files not required for the display. Consequently, the files
formed of self-descriptive can be displayed even when data storing
capacity of the receiver is small.
[0354] Further, the identifier of each file includes characters
directly being selected by the selecting condition varying means of
the receiver, and the transmission means transmits the files
packetized with identifiers uniquely assigned thereto, and the
selective receiving means selectively receives the packetized files
having predetermined identifiers in accordance with a selecting
condition set therein, and the selecting condition varying means
provides the identifier assigned to the file so as to obtain the
file specified by the reference command in the self-descriptive
data to the selective receiving means. Consequently, desired files
can be selected without using data representing correspondence
thereamong.
[0355] 3) The digital data communication system according to the
present invention is characterized in that, the system further
comprises display means for displaying the display data generated
by the display data generating means, and the selecting condition
varying means varies the selecting condition set in the selecting
means so as to select a file specified by the reference command
when one of a plurality of regions displayed on the display means
which is specified by the reference command is selected thereon.
Consequently, the files formed of self-descriptive data can be
displayed on the display means without storing files not required
for the display, while switching the display at an option of the
operator.
[0356] The digital data communication system according to the
present invention is characterized in that, the files stored in the
file storing means are divided into groups according to the
identifiers assigned thereto, and the selecting means divides the
self-descriptive data being outputted into groups by using the
identifiers and outputs the divided self-descriptive data
therefrom. In this way, for example, chargeable data can easily be
distinguished from data free of charge by just assigning different
directory names.
[0357] 4) The digital data communication system according to the
present invention is characterized in that, the data converting
means converts both the identifier of each file and an identifier
of the reference command into characters directly be selected by
the selecting means. In this way, it is not necessary to specify
the identifiers in characters directly being selected by the
selecting means when self-descriptive data of the file to be
transmitted is generated, so that the self-descriptive data can be
generated in any other type of identifiers.
[0358] 5) The digital data transmitter according to the present
invention, each of the files stored in the file storing means
consist of self-descriptive data including a reference command for
referring another file, and an identifier of the each file,
consisting of characters directly being selected by selective
receiving means in a receiver, and the transmission means transmits
the packetized files with unique identifiers. In this way, it is
not necessary to prepare data representing correspondence between
identifiers assigned to files to be selected by the receiver and
the selecting condition set in the selecting means. Consequently,
desired files can be selected at a high speed.
[0359] 6) The digital data transmitter according to the present
invention, both the identifier of the each file and an identifier
of the reference command are converted into characters directly be
selected by selecting means in the receiver according to a rule for
conversion when identifiers of the files stored in the file storing
means are provided in a form incapable of directly selecting by the
selecting means. In this way, it is not necessary to specify the
identifiers in characters directly being selected by the selecting
means when self-descriptive data of the file to be transmitted is
generated, so that the self-descriptive data can be generated in
any other type of identifiers.
[0360] 7) The digital data transmitter according to the present
invention is characterized in that, the data outputted from the
selective receiving means forms a file consisting of
self-descriptive data including a reference command for referring
another file, and the display data generating means generates
display data according to the self-descriptive data outputted by
the selective receiving means, and the selecting condition varying
means provides an identifier of a file as the selecting condition
to the selective receiving means so as to obtain the file specified
by the reference command in the self-descriptive data. In this way,
the files solely required for the display can be displayed on the
display means without storing files not required for the display.
Consequently, the files formed of self-descriptive data which refer
one another can be displayed even when data storing capacity of the
receiver is small.
[0361] 10) The digital data communication system according to the
present invention is characterized in that, the files stored in the
file storing means are divided into groups according to the
identifiers assigned thereto, and the selecting means divides the
self-descriptive data being outputted into groups by using the
identifiers and outputs the divided self-descriptive data
therefrom. In this way, the files thus received can be divided into
groups. Consequently, for example, chargeable data can easily be
distinguished from data free of charge by dividing into separate
groups.
[0362] The grouping described above can also be carried out by
substituting the identifiers assigned to the files stored in the
file storing means with both directory names and file names
belonging thereto, and the packetized files selected by the
selecting means are divided into groups under the directory basis
thereby. 11) The digital data communication system according to the
present invention is characterized in that, the files divided in
the same group are transmitted with the same packet id. In this
way, the received files can be divided into groups by using the
PID.
[0363] 12) The digital data receiver according to the present
invention is characterized in that, the selecting means divides the
packetized files selected by the selecting means into groups under
the directory basis thereby. In this way, the files thus received
can be divided into groups. Consequently, for example, chargeable
data can easily be distinguished from data free of charge by just
assigning different directory names.
[0364] 18) The method of communicating digital data according to
the present invention is characterized in that, a plurality of
files are repeatedly transmitted after packetizing the files
according to a transmission protocol with identifiers uniquely
assigned thereto in a transmitting station, each of the files
consisting of self-descriptive data including a reference command
for referring another file, the identifier of the each file
consisting of characters directly being selected by a receiving
station, and the following steps are performed in a receiving
station, the packetized files having predetermined identifiers are
selectively received in accordance with a selecting condition set
therein, and display data are generated in accordance with the
self-descriptive data contained in the packetized files and the
display data are outputted, and the identifier of the file is
varied as the selecting condition so as to obtain the file
specified by the reference command in the self-descriptive
data.
[0365] In this way, the files formed of self-descriptive data can
be displayed on the display means without storing files not
required for the display in the file storing device, while not
preparing data representing correspondence of files to be
selected.
[0366] 19) The data communication system according to the present
invention is characterized in that, the system comprises a
transmitter and a receiver,
[0367] A) the transmitter including:
[0368] a1) file storing means for storing a plurality of files,
and
[0369] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0370] B) the receiver including:
[0371] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0372] b2) received data storing means for storing data contained
in the packetized files each having same identifier in one
independent file basis,
[0373] b3) display data generating means for generating display
data according to the outputted data, and
[0374] b4) selecting condition varying means for varying the
selecting condition; and
[0375] C) wherein c1) the file storing means stores files formed of
self-descriptive data which includes a reference command for
referring another file,
[0376] c2) the transmission means assigns one module identifier
including characters capable of being read directly with the
selective receiving means to both a reference file which refers
other files and a referred file which is referred by the reference
file, and transmits the reference file and the referred file,
and
[0377] c3) the display data generating means generates display data
according to self-descriptive data contained in the reference file,
and generates another display data according to a desired referred
file which is read out thereby from the received data storing
means.
[0378] In this way, the referred file can further be selectively
received by just setting the selecting condition for selecting the
reference file without preparing data representing correspondence
between the reference file and the file to be selected.
Consequently, display data according to the reference file which
includes the referred file, can be displayed quickly. As a result,
desired files can be selected at a high speed without storing all
the files.
[0379] 20) The data receiver according to the present invention is
characterized in that, the receiver comprises selective receiving
means for selectively receiving packetized files having
predetermined identifiers in accordance with a selecting condition
set therein and outputting data contained in the packetized files,
received data storing means for storing the outputted data each
having same identifier under a file basis, display data generating
means for generating display data according to the outputted data,
and selecting condition varying means for varying the selecting
condition, wherein the packetized files thus received are one of a
reference file formed of self-descriptive data which includes a
reference command for referring another file and a referred file
which is referred by the reference file, and one identifier
including characters capable of being read directly with the
selective receiving means is assigned to these files, and wherein
display data generating means generates display data according to
self-descriptive data contained in the reference file, and
generates another display data according to a desired referred file
which is read out thereby from the received data storing means, and
wherein the selecting condition varying means varies the selecting
condition so as to selectively receive packetized files each
assigned same identifier with that of a specific reference file in
order to selectively receive the specific reference file.
[0380] In this way, the referred file can further be selectively
received by just setting the selecting condition for selecting the
reference file without preparing data representing correspondence
between the reference file and the file to be selected.
Consequently, display data according to the reference file which
includes the referred file, can be displayed quickly. As a result,
desired files can be selected at a high speed without storing all
the files.
[0381] 21) The data receiver according to the present invention is
characterized in that, file to be automatically referred can
selectively be received without setting the selecting condition for
selectively receiving the desired file to be automatically referred
as a result of reading a reference file when the reference file is
a file including an automatic reference tag. In this way, display
data of a file including the file to be automatically referred can
be generated more quickly.
[0382] 22) The data receiver according to the present invention is
characterized in that, the referred file is selectively received as
it is when selective receipt of the reference file is initiated
because the reference file and the referred file are linked with
each other.
[0383] 23) The data receiver according to the present invention is
characterized in that, the reference file and the referred file
comprise a unitized file. In this way, desired files can
selectively be received when selective receipt of the one unitized
file is initiated.
[0384] 24) The method of communicating digital data according to
the present invention is characterized in that, a plurality of
files stored in a transmitting station after packetizing the files
according to a transmission protocol are repeatedly transmitted
with identifiers uniquely assigned thereto in the transmitting
station, and the following steps are performed in a receiving
station, the packetized files having predetermined module
identifiers are selectively received in accordance with a selecting
condition set therein, data contained in the packetized files each
having same identifier are stored in one independent file basis,
and display data are generated according to the outputted data,
wherein one module identifier including characters capable of being
read directly with the receiving station is assigned to both a
reference file which refers other files and a referred file which
is referred by the reference file in the transmitting station, and
wherein the following steps are performed by the receiving station,
the selecting condition is varied so as to selectively receive
packetized files each assigned s identifier with that of a specific
reference file in order to selectively receive the specific
reference file, and display data is generated according to
self-descriptive data contained in the reference file, and
generates another display data according to a desired referred file
which is read out thereby.
[0385] In this way, the referred file can further be selectively
received by just setting the selecting condition for selecting the
reference file without preparing data representing correspondence
between the reference file and the file to be selected.
Consequently, display data according to the reference file which
includes the referred file, can be displayed quickly. As a result,
desired files can be selected at a high speed without storing all
the files.
[0386] 26) The data communication system according to the present
invention is characterized in that, the system comprises a
transmitter and a receiver,
[0387] A) the transmitter including:
[0388] a1) file storing means for storing a plurality of files,
and
[0389] a2) transmission means for repeatedly transmitting the files
packetized thereby in accordance with a transmission protocol, the
packetized files uniquely assigned identifiers;
[0390] B) the receiver including:
[0391] b1) selective receiving means for selectively receiving the
packetized files having predetermined identifiers in accordance
with a selecting condition set therein and outputting data
contained in the packetized files,
[0392] b2) received data storing means for storing data contained
in the packetized files each having same identifier in one
independent file basis,
[0393] b3) display data generating means for generating display
data according to the outputted data, and
[0394] b4) selecting condition varying means for varying the
selecting condition; and
[0395] C) wherein c1) the file storing means stores a plurality of
reference files formed of self-descriptive data which includes a
reference command for referring a plurality of other files,
[0396] c2) the transmission means assigns one module identifier
including characters capable of being read directly with the
selective receiving means to the reference files and transmits the
reference files,
[0397] c3) the display data generating means generates display data
according to self-descriptive data contained in the reference
files, and generates another display data according to desired
referred files which are read out thereby from the received data
storing means, and
[0398] c4) the selecting condition varying means uses the module
identifier as the selecting condition.
[0399] In this way, a plurality of referred files to be selected
are received as one unitized file. Consequently, display data
according to the reference file which includes the referred file,
can be displayed quickly. As a result, desired files can be
selected at a high speed without storing all the files.
[0400] 27) The digital data receiver according to the present
invention is characterized in that, the receiver comprises
selective receiving means for selectively receiving packetized
files having predetermined identifiers in accordance with a
selecting condition set therein and outputs data contained in the
packetized files, received data storing means for storing data
contained in the packetized files each having same identifier in
one independent file basis, display data generating means for
generating display data according to the outputted data, and
selecting condition varying means for varying the selecting
condition, wherein the packetized files thus received are one of a
reference file formed of self-descriptive data which includes a
reference command for referring a plurality of other files and a
referred file which is referred by the reference file, and wherein
one identifier including characters capable of being read directly
with the selective receiving means is assigned to the referred
files through the reference file, and wherein the display data
generating means generates display data according to
self-descriptive data contained in the reference file, and wherein
the selecting condition varying means varies the selecting
condition so as to selectively receive packetized files each
assigned same identifier with that of a specific reference file in
order to selectively receive the specific reference file in
accordance with data of the reference file.
[0401] In this way, a plurality of referred files to be selected
are received as one unitized file. Consequently, display data
according to the reference file which includes the referred file,
can be displayed quickly. As a result, desired files can be
selected at a high speed without storing all the files.
[0402] 28) The data receiver according to the present invention is
characterized in that, same module identifier with that of the
referred files is assigned to the reference file. In this way, the
referred file can further be selectively received by just setting
the selecting condition for selecting the reference file without
preparing data representing correspondence between the reference
file and the file to be selected. Consequently, display data
according to the reference file which includes the referred file,
can be displayed quickly. As a result, desired files can be
selected at a high speed without storing all the files.
[0403] 29) The data receiver according to the present invention is
characterized in that, the receiver comprises selective receiving
means for selectively receiving packetized files having
predetermined identifiers in accordance with a selecting condition
set therein and outputs data contained in the packetized files,
received data storing means for storing data contained in the
packetized files each having same identifier in one independent
file basis, display data generating means for generating display
data according to the outputted data, and selecting condition
varying means for varying the selecting condition, wherein the
packetized files thus received are one of a reference file formed
of self-descriptive data which includes a reference command for
referring another file and a referred file which is referred by the
reference file, and one identifier including characters capable of
being read directly with the selective receiving means is assigned
to these files, and wherein display data generating means generates
display data according to self-descriptive data contained in the
reference file, and generates another display data according to a
desired referred file which is read out thereby from the received
data storing means, and wherein the selecting condition varying
means extracts characters directly be selected by the selective
receiving means out of absolute path assigned to the referred files
and provides the characters to the selective receiving means as the
selecting condition so as to selectively receive packetized files
each assigned same identifier with that of the reference file in
order to selectively receive the reference file.
[0404] In this way, the file formed of self-descriptive data can be
displayed on the display means without storing files not required
for the display because a part of the absolute path assigned to the
referred files is used as the selecting condition. Consequently, a
file referred by another can be displayed even when data storing
capacity of the receiver is small.
[0405] Definition of words used in the appended claims, and
correspondence between these words to the words used in the
embodiments described above are as follows.
[0406] The word "receiver" is a device, at least capable of
selectively receiving a desired service contained in a desired
transport stream out of a plurality of transport streams being
transmitted. The device includes a video cassette recorder which
incorporates an apparatus so called a set-top box, or a television
set and the like having the functions of a set-top box.
[0407] The word "self-descriptive data" is data assigned its
display information such as display positions of character data,
its character size, information as to graphic data to be referred.
For example, SGML data, HTML data, XML data, data defined under
coding of multimedia and hypermedia information part 5 in ISO/IEC
15522-5 (MHEG standard) and the like are included in the
self-descriptive data.
[0408] The word "program storage medium" includes a data storing
medium storing program(s) performed by a CPU such as ROMs, RAMs,
hard disks, flexible disks, CD-ROMs and the like. Further, the
programs correspond to the memory 27 and the hard disk 26 depicted
in FIG. 2 in the embodiments described above.
[0409] While the invention has been described in its preferred
embodiments, it is to be understood that the words which have been
used are words of description rather than limitation and that
changes within the purview of the appended claims may be made
without departing from the true scope and spirit of the invention
in its broader aspects.
* * * * *
References